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Task Analysis and Heuristic Analysis of Insulin Charts Final report prepared for the Australian Commission on Safety and Quality in Health Care: 2 February 2012

Melany J. Christofidis, Mark S. Horswill, Andrew Hill, Blake M. McKimmie, Troy Visser, Marcus O. Watson

© Commonwealth of Australia 2012 This work is copyright. It may be reproduced in whole or in part for study or training purposes subject to the inclusion of an acknowledgement of the source. Requests and inquiries concerning reproduction and rights for purposes other than those indicated above requires the written permission of the Australian Commission on Safety and Quality in Health Care, GPO Box 5480 Sydney NSW 2001 or [email protected] Suggested citation Melany J. Christofidis, Mark S. Horswill, Andrew Hill, Blake M. McKimmie, Troy Visser, Marcus O. Watson, Task Analysis and Heuristic Analysis of Insulin Charts: Final report prepared for the Australian Commission on Safety and Quality in Health Care:2 February 2012. ACSQHC, Sydney. Acknowledgment ACSQHC wishes to acknowledge the contribution by health services that provided insulin charts for this analysis. This paper is available on the ACSQHC web site: www.safetyandquality.gov.au

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http://www.safetyandquality.gov.au/

Task Analysis and Heuristic

Analysis of Insulin Charts Final Report prepared for the Australian Commission on

Safety and Quality in Health Care: 2 February 2012

Melany J. Christofidis, Mark S. Horswill, Andrew Hill, Blake M. McKimmie, Troy Visser, Marcus O. Watson

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Task Analysis and Heuristic Analysis of Insulin Charts _______________________________________________________ Final Report: 2 February 2012

Contents (CTRL+ click on label to go to section)

Authors ..........................................................................................................................................5 Corresponding Author................................................................................................................................ 5

Acknowledgements........................................................................................................................5

Disclaimer ......................................................................................................................................5

List of Tables (CTRL + click on caption to go to table)......................................................................6

List of Figures (CTRL + click on caption to go to figure) ..................................................................8

1. Project Aims and Summary ......................................................................................................10

2. Project Background ..................................................................................................................11 2.1. Diabetes Mellitus ...............................................................................................................................11

2.2. Blood Glucose Control ........................................................................................................................11

2.3. Insulin Therapy...................................................................................................................................11

2.3.1. Intravenous Insulin Therapy ............................................................................................................ 11

2.3.2. Subcutaneous Insulin Therapy ........................................................................................................ 12

2.4 Insulin Charts ......................................................................................................................................12

3. Project Methods.......................................................................................................................13 3.1. Phase I: Informal task analysis............................................................................................................13

3.1.1. Initial analysis of 37 insulin charts................................................................................................... 14

3.1.2. Structured interviews ...................................................................................................................... 14

3.1.3. Observations.................................................................................................................................... 14

3.2. Phase II: Heuristic analysis..................................................................................................................15

3.2.1. Evaluators ........................................................................................................................................ 15

3.2.2. Insulin charts ................................................................................................................................... 15

3.2.3. Heuristic analysis procedure ........................................................................................................... 16

4.0 Insulin Chart Protocol .............................................................................................................17 4.1 Identification and demographics .........................................................................................................17

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4.2 Blood glucose monitoring frequency ...................................................................................................17

4.3 Alerts and special instructions .............................................................................................................18

4.4. Initial blood glucose monitoring .........................................................................................................18

4.5 Initial insulin orders and insulin administration ...................................................................................18

4.6 Continued blood glucose monitoring and adjusted insulin administration ...........................................18

4.7 Response to hypoglycaemic and hyperglycaemic events......................................................................19

5. Usability issues identified in the Heuristic Analysis ..................................................................20 5.1. Page and information layout ..............................................................................................................20

5.2. Cognitive and memory loads .........................................................................................................27

5.3. Recording of blood glucose levels .................................................................................................30

5.4. Alerting systems .............................................................................................................................36

5.5. Action systems ................................................................................................................................42

5.6. Language and labelling .......................................................................................................................46

5.7. Font ..................................................................................................................................................49

5.8. Colour...............................................................................................................................................52

6. Usability Issues and Potential Design Solutions ........................................................................55 6.1. Monitoring of blood glucose levels .....................................................................................................55

6.1.1. Displays of blood glucose ................................................................................................................ 55

6.1.2. Blood glucose alerting systems ....................................................................................................... 58

6.1.3 Frequency of blood glucose monitoring........................................................................................... 59

6.2. Administration of insulin ....................................................................................................................61

6.2.1. Delayed subcutaneous insulin administration ................................................................................ 61

6.2.2. Administering an incorrect subcutaneous dose.............................................................................. 63

6.2.3. Supplemental insulin as a sliding scale............................................................................................ 65

6.3. Prescription of insulin.........................................................................................................................67

6.3.1. Subcutaneous routine insulin orders .............................................................................................. 67

6.3.2. Intravenous fixed insulin orders ...................................................................................................... 68

6.3.3. Intravenous variable insulin orders ................................................................................................. 69

6.3.4. Subcutaneous standing supplemental insulin orders ..................................................................... 72

6.3.5 Incorrect use of Stat/Phone order.................................................................................................... 73

6.4. General presentation considerations..................................................................................................76

6.4.1. Chart title area and headings .......................................................................................................... 76

6.4.2. Use of abbreviations........................................................................................................................ 77

6.4.3. Clinicians’ initials ............................................................................................................................. 78

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6.4.4. Prescribers’ details .......................................................................................................................... 78

7. Proposed Research Programme for Developing and Evaluating Insulin Charts .........................80 7.1. Phase 1: Develop new charts with associated preliminary instructional material................................80

7.2. Phase 2: Empirical experiments to assess user performance with the new charts, compared with one

another and with existing charts ...............................................................................................................81

7.3. Phase 3: User acceptance studies .......................................................................................................82

7.4. Phase 4: Development and validation of the full training packages.....................................................84

7.5. Final outcomes of research programme..............................................................................................84

References ...................................................................................................................................86

Appendix A: Insulin charts submitted by the Australian Commission on Safety and Quality in Health Care. .................................................................................................................................88

Appendix B: Features analysed in the preliminary descriptions of the Informal Task Analysis......89

Appendix C: Representative charts selected for Heuristic Analysis...............................................94

Appendix D: Briefing report for evaluation team........................................................................110

Appendix E: Usability considerations, customized for insulin charts...........................................122

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Authors Project Manager Miss Melany J. Christofidis School of Psychology, The University of Queensland Chief Investigator Associate Professor Mark S. Horswill School of Psychology, The University of Queensland Senior Consultant Dr Andrew Hill School of Psychology, The University of Queensland Clinical Skills Development Service, Queensland Health Senior Consultant Dr Blake M. McKimmie School of Psychology, The University of Queensland Senior Consultant Dr Troy Visser School of Psychology, The University of Queensland Principal Investigator Associate Professor Marcus O. Watson Clinical Skills Development Service, Queensland Health School of Medicine, The University of Queensland Corresponding Author Associate Professor Mark S. Horswill School of Psychology, The University of Queensland St Lucia, Queensland, 4072 (07) 3346 9520 [email protected] Acknowledgements We would like to thank Graham Bedford from the Australian Commission on Safety and Quality in Health Care and all of the interested parties who provided insulin charts for inclusion in the current study. Thanks also go to Fiona McIver and Carol Reid from Medication Services Queensland, Karen Boch from Queensland Health, Dr Joey Kaye from WA Endocrine Health Network, and Associate Professor Maarten Kamp from The University of Queensland, for their valuable advice and help in relation to insulin chart functions and protocols. We would also like to thank Elizabeth Stewart for research assistance. Disclaimer The potential solutions suggested in this report (Section 6) to address the usability problems identified with existing insulin charts (Section 5) must be considered preliminary until they can be implemented as part of a complete chart design and then empirically tested (which is not part of the current project brief). However, as part of this report (Section 7), we have outlined the programme of research that would be necessary to do this (in which we propose developing a number of alternative design solutions and testing these solutions against one another in behavioural experiments to obtain empirical evidence to determine which design yields the fewest errors in the shortest time when users are completing representative chart‐related tasks). Also, it is important to note that the figures provided to demonstrate the suggested design solutions (Section 6) are only intended for illustrative purposes and do not represent what a complete best‐practice insulin chart would eventually look like.

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List of Tables (CTRL + click on caption to go to table)

Table 1: Characteristics of the seven evaluators..............................................................................................15

Table 2: List of insulin charts in the Heuristic Analysis................................................................................16

Table 3: Usability problems affecting page and information layout, rationales for the underlying design rules and specific examples from each chart ..............................................................20

Table 4: Usability problems related to cognitive and memory loads, rationales for the underlying design rules and specific examples from each chart ..............................................................27

Table 5: Usability problems related to recording of blood glucose levels, rationales for the underlying design rules and specific examples from each chart ..............................................................30

Table 6: Usability problems related to alerting systems (anything that provides cues to the chart user that indicate when something is wrong, such as the notification of abnormal BGLs), rationales for the underlying design rules and specific examples from each .....................................36

Table 7: Usability problems related to action systems (anything that assists the user to take appropriate critical actions, such as the frequency of actions or the integration of a recommended dosage), rationales for design rules and examples from each chart........................42

Table 8: Usability problems related to language and labelling, rationales for the underlying design rules and specific examples from each chart ......................................................................................46

Table 9: Usability problems related to the use of fonts, rationales for the underlying design rules and specific examples from each chart.....................................................................................................49

Table 10: Usability problems related to the use of colour, rationales for the underlying design rules and specific examples from each chart.....................................................................................................52

Table 11: Percentage of charts that utilise various presentations of blood glucose levels...........89

Table 12: Percentage of charts that utilise various altering systems .....................................................89

Table 13: Percentage of intravenous charts that provide normal BGL ranges...................................89

Table 14: Percentage of subcutaneous charts that provide normal BGL ranges ...............................89

Table 15: Percentage of charts that utilise various presentations of blood glucose frequency indicators...........................................................................................................................................................................90

Table 16: Percentage of charts that utilise various presentations of insulin administration records, relative to blood glucose levels..............................................................................................................90

Table 17: Percentage of charts that utilise various lengths (in hours) of BGL monitoring record................................................................................................................................................................................................90

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Table 18: Percentage of subcutaneous charts that specify when to record BGL, relative to mealtime............................................................................................................................................................................90

Table 19: Percentage of subcutaneous charts that utilise various presentations of routine insulin orders, relative to insulin administration records...........................................................................91

Table 20: Percentage of charts that provide distinction between subcutaneous and intravenous insulin therapy................................................................................................................................................................91

Table 21: Percentage of charts that preprint insulin ‘units’ or chart user ‘initials’ ..........................91

Table 22: Percentage of charts that utilise various abbreviations and forms of clinician authorisation ...................................................................................................................................................................92

Table 23: Percentage of charts that utilise various colours for different purposes .........................93

Table 24: Percentage of charts that utilise various presentations of patient identification.........93

Table 25: Percentage of charts that utilise various paper size, orientation, and sidedness .........93

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List of Figures (CTRL + click on caption to go to figure)

Figure 1: Example of a BGL record displayed as a quasi‐graph. Scales are presented on the left and right; bold vertical lines are placed every three time columns; right‐aligned values in the left‐hand‐side scale; left‐aligned in the right‐hand‐side scale; values formatted the same as one another; and values formatted differently from the variable label. ........................................................57

Figure 2: Example of a BGL record with a single parameter colour coded track and trigger system, with intuitive colour and density progression.................................................................................59

Figure 3: Example of a BGL record with BGL monitoring tick‐boxes provided for each day. ......61

Figure 4: Example of an insulin administration record aligned directly below a BGL record.....63

Figure 5: Example of a BGL record’s colour coded range rows aligned with the corresponding colour coded blood glucose range rows of a supplemental insulin order record. ............................64

Figure 6: Example of a supplemental insulin administration record presented immediately beneath a routine insulin administration record, with aligned date and time columns. ...............65

Figure 7: Example of a supplemental insulin order record presented to the right of a routine insulin order record......................................................................................................................................................66

Figure 8: Example of supplemental insulin orders presented below routine insulin orders. .....67

Figure 9: Example of the date columns of a BGL record directly aligning with the date columns of a routine insulin order record. ...........................................................................................................................68

Figure 10: Example of a BGL record’s colour coded range rows aligned with the corresponding colour coded blood glucose range rows of an adjustment of insulin infusion guideline. ..............70

Figure 11: Example of an algorithm for insulin adjustments separated into three separate tables based on current insulin rate, utilising colour coded blood glucose range rows that correspond to the colour coded range rows of a BGL record’s track and trigger system..............71

Figure 12: Example of algorithm for insulin adjustments presented adjacent to a BGL record and insulin administration record, on an A3 sized (landscape orientation) chart. ..........................72

Figure 13: Example of visually separated routine insulin orders and supplemental insulin orders..................................................................................................................................................................................73

Figure 14: Example of an insulin administration record presented after insulin orders records, including stat/phone insulin orders......................................................................................................................74

Figure 15: Example of a stat/phone insulin order presented to the right of routine and supplemental insulin order records. .....................................................................................................................75

Figure 16: Example of a chart title including insulin route (presented in bold font) and patient population.........................................................................................................................................................................76

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Figure 17: Example of headings presented white font on a black background, and with corresponding symbols...............................................................................................................................................77

Figure 18: Example of insulin dose cells with pre‐printed units, with visually differentiated rows. ....................................................................................................................................................................................78

Figure 19: Example of an independent table for prescribers to record their name, signature and initials. ................................................................................................................................................................................79

Figure 20: Front and reverse pages of Queensland Insulin Intravenous Infusion Order and Blood Glucose Record – Adult (A4)........................................................................................................................94

Figure 21: Front and reverse pages of Fremantle Hospital and Health Service Insulin Infusion Chart (A4)..........................................................................................................................................................................96

Figure 22: Outside and inside pages of Sydney West Blood Glucose Level (BGL) monitoring chart for IV Insulin Infusions (A3) .........................................................................................................................98

Figure 23: Outside and inside pages of Queensland Insulin Subcutaneous Order and Blood Glucose Record – Adult (A3).................................................................................................................................. 100

Figure 24: Front and reverse pages of Tasmania Blood Sugar Record and Insulin Order (A4)102

Figure 25: Outside and inside pages of Sydney West Adult Subcutaneous Insulin Prescribing Chart (A3)....................................................................................................................................................................... 105

Figure 26: Mt Gambier Frequent/Variable Medication Chart (A4, one sided) ................................ 107

Figure 27: Outside and inside pages of Northeast Health Wangaratta Regular Medications chart (A3) ................................................................................................................................................................................... 108

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1. Project Aims and Summary The current project used a human factors approach to generate proposals for improving the design of adult insulin charts. The aims of the project were: 1. To identify potential usability problems that might arise as a result of insulin chart design.

This included identifying practices, procedures, functions, and measures associated with insulin charts.

2. To identify design problems affecting a range of existing charts, in order to generate proposals as to what might represent best practice in the design of insulin charts.

3. To offer recommendations, in light of the findings, as to whether a new chart design is warranted, or whether one of the existing charts already appears to represent best practice.

4. To use this information to design a potential program of research to test the validity of the proposals about best practice as well as developing (if necessary) and validating best‐practice subcutaneous and intravenous insulin charts, with associated training. This research programme would include performance experiments to measure the accuracy and speed of performing key tasks with competing chart designs and also user acceptance studies.

We identified a range of usability problems with existing insulin charts, which are likely to lead to user error. Our key recommendation therefore is that new insulin charts be developed using the best current charts as a starting point. We have described a number of design solutions that could be incorporated into these new charts in order to reduce errors. We have also outlined one potential strategy for a follow‐up programme of research to develop and empirically evaluate some alternative designs of new insulin charts in order to allow us to produce best‐practice subcutaneous and intravenous insulin charts. This potential line of research will include the development and validation of training packages to accompany the charts, which will consist of both instructional material and persuasive communications to maximize user acceptance of and compliance with the new charts.

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2. Project Background 2.1. Diabetes Mellitus Diabetes mellitus is a group of metabolic diseases caused by an absolute or a relative lack of the pancreatic hormone, insulin (Guthrie & Guthrie, 2008; Watkins, 2002; Gottschlich, 2001). The vast majority of diabetic cases fall into two broad categories: Type 1, caused by an absolute deficiency of insulin secretion; and Type 2, the result of a combination of resistance to insulin action and an inadequate compensatory insulin secretory response (Gottschlich, 2001). The prevalence of diabetes mellitus in Australia is trending upwards, increasing from 2.4% in 1995, to 3.0% in 2001, and 3.5% in 2005 (Australian Bureau of Statistics, 2009a). This rise is cause for concern given that diabetes can contribute to illness, disability, poor quality of life, and premature death. Indeed, diabetes contributed to 10.1% of Australian deaths in 2009, as either an underlying or associated cause (Australian Bureau of Statistics, 2009b). Two different conditions can lead to a diabetic emergency: hyperglycaemia, a state in which an individual’s blood glucose level (BGL) is above normal physiological ranges; and hypoglycaemia, a state in which an individual’s BGL is below normal physiological ranges. Ketoacidosis results from prolonged and exceptionally high hyperglycaemia, whilst loss of consciousness and eventual insulin shock result from hypoglycaemia (Pollak et al., 2006). 2.2. Blood Glucose Control It has been estimated that between 1 in 8 and 1 in 4 adult hospital inpatients in Australia has diabetes (Bhattacharya et al., 2002; Clement et al., 2004; Metchick, Petit, & Inzucchi, 2002). Diabetic patients need targeted glycaemic control when they are in hospital, arguably more than when at home, considering the stresses of critical illness and surgery when hospitalised (Moghissi, 2004). A rapidly growing body of literature suggests that, regardless of whether a patient has a known history of diabetes, in‐hospital hyperglycaemia is associated with increased mortality and morbidity. As such, meticulous glycaemic control can significantly improve clinical outcomes (Cheung & Chipps, 2010; Guthrie & Guthrie, 2008; Pomposelli et al., 1998; Zerr et al., 1997). 2.3. Insulin Therapy Insulin is the most effective agent for achieving glycaemic control in hospitalised patients (Moghissi, 2004). It can be titrated easily, does not have a ceiling dose, and can be administered intravenously (though the vein) or subcutaneously (under the skin) (Barnard, Batch & Lien, 2011). Inpatient insulin regimens must be matched or tailored to the specific clinical circumstance of the individual patient (Clement et al., 2004). Indications for intravenous (IV) insulin therapy include prolonged fasting, critical illness, pre surgical procedures, post organ transplantations, and during labour (Moghissi, 2004; Clement et al., 2004). In these patients, the intravenous route for insulin administration surpasses the subcutaneous route because of its rapid onset, effect in controlling hyperglycaemia, and overall ability to achieve glycaemic control. Subcutaneous (SC) insulin therapy is used to attain glucose control in those diabetic patients who do not fall under the aforementioned intravenous categories (Clement et al., 2004), and is therefore the more common route of insulin administration. 2.3.1. Intravenous Insulin Therapy

A number of protocols have been developed to assist with titration of intravenous insulin infusion rates, and most hospitals have a preferred order set. Clinically favoured

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methods take into account patients’ insulin‐sensitivity levels (Lien, Feinglos & Corsino, 2010). One way to achieve this is to adjust the insulin infusion according to the rate of change of glucose levels from hour to hour, using a multiplication factor to assist with titration. Other IV insulin protocols account for differences in patients’ insulin sensitivities by using a choice format (with the appropriate algorithm chosen according to level of sensitivity) (Lien, Feinglos & Corsino, 2010). Despite the effectiveness of intravenous insulin protocols for most patients, it is worth noting that there are patients for whom no protocol is perfect. An example is the highly insulin‐resistant patient, who may require large volumes of intravenous insulin. Similarly, the highly insulin‐sensitive patient, particularly those with renal failure and Type 1 diabetes, may require very small volumes of insulin. This type of patient will require the attention of an experienced prescriber, rather than just the application of a protocol (Lien, Feinglos & Corsino, 2010).

2.3.2. Subcutaneous Insulin Therapy

Evidence suggests that subcutaneous insulin administration should include three components to be effective: basal insulin (to inhibit hepatic glucose production overnight and between meals), bolus insulin (to facilitate mealtime glucose metabolism), and correction‐dose insulin (to provide real‐time adjustment of insulin dosing based on a patient’s insulin sensitivity) (Nau et al., 2010; Hirsch, 2009). Correction‐dose insulin is usually administered as an addition (or supplement) to the routine dose of bolus insulin using a specific algorithm based on total daily dose of insulin or patient weight (Hirsch, 2009). The correction‐dosing approach can be illustrated by a diabetic patient treated with routine insulin (e.g., 10 units at each meal), whose BGL increases by a clinically significant amount; the attending clinician can add extra insulin (e.g., 2 units) to the patient’s routine insulin (i.e., 10 + 2 = 12 units) to bring their glucose levels back down to an acceptable level. Similarly, if the patient’s glucose levels are too low, the clinician can subtract an appropriate number of insulin units. Correction‐dose insulin is often confused with “sliding scale” insulin; however the difference between the two is crucial (Hirsch, 2009). Sliding scale insulin refers to subcutaneous insulin doses administered to reduce hyperglycaemia detected on routine blood glucose monitoring. Once again, the sliding scale approach can be illustrated by a diabetic patient with elevated blood glucose levels. For example, the sliding scale may specify that if the patient’s BGL is between 10 and 14.9 mmol/L then the attending clinician should administer 6 units of insulin, if it is between 15 and 19.9 mmol/L, then 8 units, or if it is over 20 mmol/L, 10 units. In contrast to the correction‐dose approach, this sliding scale insulin is the only insulin the patient receives. Sliding‐scale insulin regimens incorrectly assume that all patients have similar insulin sensitivities, fail to adequately control hyperglycaemia, result in high rates of hypoglycaemia, and are associated with longer hospital stays (Queale, Seldler & Brancati, 1997). Perhaps more importantly, sliding scales have no demonstrated track record of effectiveness. A Medline search of 52 trials from 1966 to 2003 yielded no evidence of a clinical benefit from sliding scale insulin (Hirsch, 2009).

2.4 Insulin Charts Intravenous and subcutaneous insulin charts – used by both medical officers and nurses – are the primary method of monitoring a patient’s blood glucose levels, and documenting the

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associated insulin therapy during hospital stays. Despite their potential to help clinicians maintain targeted glycaemic control, which is the primary objective of diabetic management, Australian insulin charts vary widely in their design. Empirical evidence has demonstrated that the design of patient observation charts can significantly affect a user’s decision time and accuracy when detecting abnormal physiological observations (Horswill et al., 2010). By extension, this suggests that differences between insulin chart designs may affect the quality of care provided to diabetic patients. In recent years, there have been calls for a national insulin chart that embodies current best practice. However, there is presently controversy as to what constitutes best practice for insulin chart design, and nationwide agreement has not been reached. In the task analysis interviews carried out for the present project, endocrinologists acknowledged that the multi‐functional nature of insulin charts means that their design is difficult. Unlike most charts used in hospital settings, insulin charts typically act as (1) as a physiological observation tool, (2) a record of drug prescription, (3) a record of drug administration; (4) a record of the physiological outcome of drug administration, and (5) a clinical practice guideline to manage diabetes. Another important consideration noted by practicing endocrinologists, is that insulin charts need to be designed for the full spectrum of health professionals. In other words, the chart must be usable for a wide variety of staff, ranging from staff specialists to junior doctors and inexperienced enrolled nurses who are unfamiliar with diabetes and the management of insulin (source: task analysis interviews with clinicians). To date, only one known investigation has evaluated the impact of insulin chart design on the management of hospitalised patients with diabetes (Lehnbom et al., 2009). In a retrospective study comparing the management of three groups of diabetic patients, Lehnbom and colleagues compared the use of insulin and the management of hypoglycaemic events before and after the introduction of a new insulin chart. The new chart allowed the documentation of insulin prescription, sliding scale insulin, blood glucose levels and hypoglycaemic events. Although significantly more hypoglycaemic events were treated post‐implementation of the new insulin chart, the number of hypoglycaemic events without any documented treatment remained unchanged, as did the number of insulin dose omissions, and cross‐referencing between the new chart and standard medication chart was performed incorrectly for over half of patients. 3. Project Methods 3.1. Phase I: Informal task analysis An informal task analysis was used to document the practices, procedures, functions, and measures associated with insulin charts (note that, from the research team’s perspective, an extensive formal task analysis, which would have been considerably more time‐consuming and costly, was not necessary). The task analysis involved creating systematic descriptions of existing insulin charts, interviewing health professionals and subject‐matter experts regarding chart use, as well as observing individuals performing typical tasks involving the charts.

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3.1.1. Initial analysis of 37 insulin charts

Thirty‐seven insulin charts that were in use, or were being considered for use, in Australia were submitted for inclusion in the study (see Appendix A). A preliminary analysis of each chart was carried out by a trained human factors evaluator. Systematic descriptions were collected based on a comprehensive list of insulin chart features (see Appendix B). From the results of the preliminary descriptions, the evaluator identified a subset of eight insulin charts (see Table 2 below for a list of the eight charts and see Appendix C for images of the charts) to be subjected to the heuristic analysis, which were selected to be as representative as possible of the full range of designs submitted. This process was then audited by a second evaluator.

3.1.2. Structured interviews

Subject‐matter experts and key stakeholders identified by the Australian Commission on Safety and Quality in Health Care were interviewed. First, the research team held two separate meetings with Fiona McIver and Carol Reid from Medication Services Queensland to document basic issues surrounding the use of insulin charts. These included protocols for using the charts, background information regarding the use of insulin and the hospital environment in which it is administered, and potential errors that might occur when using the chart (including likely consequences). Fiona McIver also provided further comments on a selection of different insulin charts. Three members of the research team then consulted with endocrinologists, Dr Joey Kaye and Associate Professor Maarten Kamp, who had previously contributed to the development of different insulin chart designs included in the study: the Fremantle Insulin Chart (or, more specifically, a Western Australian chart upon which the Fremantle Insulin chart is closely modelled) and the Queensland Insulin Charts, respectively. Dr Kaye and Associate Professor Kamp discussed the advantages and disadvantages of a range of different chart designs (electronic copies of the eight insulin charts were sent to them via email before the interview). Their perspectives were documented to ensure that existing controversies in insulin chart design were acknowledged.

3.1.3. Observations

Four members of the research team informally observed nurses and endocrinologists performing tasks involving intravenous and subcutaneous insulin charts in a tertiary hospital in order to gain a practical insight into the context in which insulin charts are used. The sessions were conducted in the morning (6:30am – 10:30am) and afternoon (11:00am – 3:00pm), across six wards. The research team observed and noted the processes by which nurses accessed patients’ medical folders, referred to ward time plans and patients’ notes, measured and documented patients’ blood glucose levels, and administered and documented subcutaneous and intravenous insulin. Also noted was the way in which endocrinologists assessed patients’ conditions, and started or adjusted insulin prescriptions. Incidental hospital protocols were also observed, including the administration of patients’ meals and staff changeovers.

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3.2. Phase II: Heuristic analysis A heuristic analysis is a form of usability inspection in which evaluators examine the usability‐related aspects of a system or how well the average user can successfully interact with the system (Mack & Nielsen, 1994; Nielsen & Mack, 1994). We used this technique to identify design problems with the subset of eight insulin charts selected from the initial analysis of 37 charts described above. 3.2.1. Evaluators

Seven evaluators were selected in order to incorporate a wide range of human factors, applied cognitive psychology, and diabetes management expertise in the group. All evaluators had previous experience in evaluating medical charts (see Table 1).

Table 1: Characteristics of the seven evaluators Evaluator Sex Age

in years

Relevant domains of expertise

Previous experience with medical charts

1 Male 43 Human factors, medical education, cognitive systems engineer

Multiple medical charts.

2 Male 41 Applied cognitive psychology, human factors, psychometrics, statistics

General observation charts, Clozapine titration chart

3 Male 37 Applied cognitive psychology, human factors, comparative cognition, research methodology

General observation charts, Clozapine titration chart

4 Male 38 Cognitive psychology, human factors

Clozapine titration chart

5 Male 38 Cognitive psychology, human factors

Clozapine titration chart

6 Female 24 Applied cognitive psychology, human factors

General observation charts

7 Female 48 Nursing, diabetes education Insulin charts and other medication charts

3.2.2. Insulin charts

All seven evaluators received two copies of each of the eight insulin charts: one blank and another with observations recorded for a diabetic patient. It was reasoned that, because insulin charts are domain‐dependent systems, the evaluation would benefit from a typical usage scenario (Nielsen and Mack, 1994). A diabetic patient’s BGL observations, insulin administration and insulin orders (where appropriate) were plotted on each chart. On those charts with example intravenous insulin therapy (see Table 2), BGL recordings were plotted for 13 time points across a single day. On those charts with example subcutaneous insulin therapy (see Table 2), BGL recordings were plotted for 20 time points across 4 days. Each set of observations reflected a diabetic patient’s typical physiology whilst in hospital, and a typical insulin dosage response from clinicians. Note that two of the charts were not specifically designed for the management of diabetic patients. However, these charts were included in the heuristic

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analysis because it is acknowledged that some hospitals utilise charts of this kind to fulfil this function. Thus it is important to interpret the findings associated with these charts in the context of diabetic management only.

Table 2: List of insulin charts in the Heuristic Analysis

Chart title Insulin therapy

Plotted example insulin therapy

Refer to figures

(Appendix C)

Queensland Insulin Intravenous Infusion Order and Blood Glucose Record ‐ Adult

Intravenous Intravenous Figure 20

Fremantle Hospital and Health Service Insulin Infusion Chart


Sydney West Blood Glucose Level (BGL) monitoring chart for IV Insulin Infusions


Queensland Insulin Subcutaneous Order and Blood Glucose Record – Adult

Subcutaneous Subcutaneous Figure 23

Tasmania Blood Sugar Record and Insulin Order


Sydney West Adult Subcutaneous Insulin Prescribing Chart


Mt Gambier Frequent/Variable Medication Chart

Not specified Intravenous Figure 26

Northeast Health Wangaratta Regular Medications

Not specified Subcutaneous Figure 27

3.2.3. Heuristic analysis procedure

The outcomes of the task analysis formed the basis of a briefing report that was distributed to the evaluation team (see Appendix D_Appendix_D: Briefing), and were also used develop the context‐specific design usability principles to be considered in the heuristic analysis. These design heuristics, customized for insulin charts, were adapted from a previous list created for a heuristic analysis of adult observation charts (Preece et al., 2009). Each heuristic was represented in a list of usability considerations that was prepared for use by the evaluators (see Appendix E). A session was held to provide evaluators with the briefing report and two paper copies of each insulin chart (one blank, and one containing patient data). The evaluators reviewed each of the charts independently, in a pre‐defined order that was different for each evaluator. Three of the evaluators were randomly assigned to review the subcutaneous charts and then the intravenous charts, while the other four evaluators reviewed the intravenous charts followed by the subcutaneous charts. Within each chart‐type (subcutaneous or intravenous), the order of charts was randomised separately for each evaluator. A tabulated document was provided to assist with the evaluation.

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Each row in the table was framed as a question about a specific usability problem (see Appendix E), to which an evaluator could respond no problem, potential problem or not applicable. However, evaluators were also encouraged (a) to provide open‐ended comments in relation to each specified usability issue, and (b) to draw on their own areas of expertise, rather than confining their comments to those specific usability issues. Subsequently, one of the evaluators combined these electronic documents to produce a single report outlining the design problems identified in relation to each chart. Finally, the evaluators participated in a debrief session. Each evaluator independently ranked the charts from best‐ to worst‐designed within each chart‐type (subcutaneous and intravenous). In light of the consensus reached over the best‐designed chart of each type, the evaluators provided and discussed suggestions to improve these charts from a human factors perspective.

4.0 Insulin Chart Protocol Before usability issues are considered, it is important to note the key steps that nurses (and medical officers/prescribers, where appropriate) take during the management of a diabetic patient. Where necessary, the protocol branches into steps that are applicable either to intravenous or to subcutaneous insulin therapies. Although largely derived from Queensland Health guidelines (QH, 2008) and our task analysis, the protocol has been generalized to apply to most insulin chart designs. 4.1 Identification and demographics

1. Establish the need for either intravenous insulin or subcutaneous insulin and select the appropriate chart.

2. Apply a patient identification label or (if unavailable) document the patient’s name, reference number, date of birth, gender and address in the patient identification section of the chart.

3. The first prescriber must print the patient’s name under the patient identification label (to reduce the risk of the wrong patient’s identification label being placed on the form).

4. Document the Facility/Service, Year, and Ward/Unit. 5. Cross reference with the Inpatient Medication Chart, by indicating that the Insulin

Chart is in use. 6. Also cross reference with the Regular Medication Order (on the Inpatient

Medication Chart) to ensure that staff refer to the insulin chart (e.g. “See insulin/BGL form”) and that insulin is not omitted from discharge medications.

4.2 Blood glucose monitoring frequency

7. Prescriber to indicate the initial frequency in which BGL will be monitored. The BGL frequency should be reviewed and updated regularly (and re‐recorded appropriately).

Intravenous: hourly BGL monitoring is typically required. Subcutaneous: BGL monitoring before meals and bed is typically required. 8. Document the diet the patient is to receive for the day.

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4.3 Alerts and special instructions

9. If not already indicated on the chart, document the target BGL range for the patient, and whom to notify if any BGL is out of target range.

Intravenous: BGL target range for most patients is 5‐10 mmol/L. Subcutaneous: BGL target range for most patients is 4‐8 mmol/L. 10. If patient requires tighter control of their BGL (e.g. due to pregnancy), special

management, or received insulin treatment prior to admission, use the communication areas (e.g. Alerts and/or Special Instructions areas).

4.4. Initial blood glucose monitoring

11. Document the date and time in the first column/row of the BGL record. 12. Measure the patient’s BGL as per facility procedure. For example: put on gloves; if

appropriate, calibrate the machine for the batch of test strips; turn on the machine and wait for the flashing “blood drop” icon; occlude blood flow by squeezing finger; prick finger; give patient a swab for the blood; insert the test strip into the machine and wait for result) (source: task analysis).

13. Record the BGL observation. 4.5 Initial insulin orders and insulin administration Intravenous Initial Infusion Rate:

14. After performing and documenting the BGL, Medical Officer to prescribe insulin infusion rate. Depending on Medical Officer and/or chart design, prescriber may decide on infusion rate based on experience, refer to recommended initial insulin infusion rates based on patient’s BGL, or calculate rate using a formula based on Type 1 patient’s usual total daily dose.

15. Medical Officer to start insulin infusion and document date/time commenced. 16. Document the rate at which the insulin infusion is running in the Insulin

Administration record. Subcutaneous Routine Insulin:

13. After performing and documenting the BGL, Medical Officer to prescribe the appropriate daily orders in Routine Insulin Orders (prescriber typically decides on routine doses based on experience) and appropriate correction dose orders in Supplemental Insulin Orders. Depending on Medical Officer and/or chart design, prescriber may decide on correction dose orders based on experience, or recommended initial correction doses based on patient’s BGL.

14. Meal times determine routine subcutaneous insulin rates. After the patient’s meal has arrived but before the patient has started eating, administer routine insulin dose.

15. Document the dose and type of insulin administered in the Insulin Administration record.

4.6 Continued blood glucose monitoring and adjusted insulin administration

16. Measure and document BGL at the next time point (indicated by the determined BGL frequency initially documented). If BGL is out of target range, adjust insulin administration appropriately. Intravenous adjustments:

19

• Depending on Medical Officer and/or chart design, prescriber may decide on revised infusion rates based on experience, or refer to an algorithm for insulin adjustments.

• Medical Officer to adjust insulin infusion and document the rate at which the insulin infusion is running in the Insulin Administration record

Subcutaneous adjustments: • Patients may require a correction dose of insulin if their condition, dietary

intake, or a concurrent medication alters their insulin requirements (or if the patient has recently commenced subcutaneous insulin and optimal doses have not yet been determined). This may be in addition to a routine insulin dose.

• Document the meal/time at which insulin is administered, as well as the type and dose of insulin administered based on the prescribed doses provided by Medical Officer.

4.7 Response to hypoglycaemic and hyperglycaemic events

Intravenous response: • If BGL is abnormally low (e.g., less than 4 mmol/L), suspend the insulin infusion,

continue glucose infusion, initiate hypoglycaemia management (refer to Hypoglycaemia Management protocol), notify prescriber, and document that hypo intervention has been initiated. Perform follow up BGLs according to Hypoglycaemia Management protocol and document treatment and response in medical record. Once hypoglycaemia is resolved, recommence insulin infusion and review insulin orders.

• If BGL is abnormally high (e.g., greater than 15 mmol/L) check that the insulin infusion is running, and notify prescriber. Prescriber to adjust insulin infusion rate. Perform a ketone test, document the result, and notify the prescriber accordingly.

Subcutaneous Response: • If BGL is abnormally low (e.g., less than 4 mmol/L), initiate hypoglycaemia

management (refer to Hypoglycaemia Management protocol), notify prescriber, and document that hypo intervention has been initiated. Perform follow up BGLs according to Hypoglycaemia Management protocol and document treatment and response in medical record.

• If BGL is abnormally high (e.g., greater than 20 mmol/L), notify the prescriber, perform a ketone test, document the result, and document the actions taken in the medical record.

• Stat/Phone Insulin Orders are made if the prescriber wants to be contacted with a BGL reading prior to prescribing an insulin dose, or If the patient has been receiving insulin and no dose is ordered, the nurse must call the treating prescriber or the Medical Officer On‐Call for a phone order (the previous day’s order is not a recurrent dose order). In both situations, the nurse writes documents that a phone order has been taken in the Stat/Phone order record.

5. Usability issues identified in the Heuristic Analysis In this section, we present the outcomes of the heuristic analysis carried out on the subsample of four intravenous (IV) and four subcutaneous (SC) insulin charts included in the analysis. The independent responses of the evaluators have been combined to produce a single report, which is detailed in the following tables (Tables 3 to 10). Usability problems have been grouped into eight broad categories: (1) page and information layout, (2) cognitive and memory loads, (3) recording of blood glucose levels, (4) alerting systems, (5) action systems, (6) language and labelling, (7) font, and (8) colour. Copies of the eight reviewed insulin charts can be seen in Appendix C. In addition to the issues raised below, the evaluators also independently indicated which chart they preferred. All seven evaluators independently selected the Queensland charts for both subcutaneous and intravenous options. 5.1. Page and information layout Table 3: Usability problems affecting page and information layout, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart

Mt Gambier Medication Chart

Wangaratta Medication Chart

Noncritical information displayed in an unnecessaryily prominent way. Non‐critical information will compete for the user’s attention.

N/A. Redundant use of the term ‘Guidelines’ in headings. Various chart codes (‘MR 850’ and ‘FH331 08/06’) presented on front page.

Prominent ‘Algorithm for insulin adjustments’ table may draw user’s attention. Chart code (‘SWHR‐2733’) presented at top of back page.

N/A. Hospital logo, chart title, and identification record obscures important notice (‘routine insulin is to be prescribed on medication chart’).

Chart code (‘SWHR‐2734’) presented at top of inside and outside pages.

Chart code (‘MGH29’) presented at top of page.

Chart code (‘UR 25‐02’) presented with chart title, vertically on front page edge.

21

Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Mixture of vertically and horizontallyoriented data points or text. Chart should not have to be turned during use. Vertical text takes longer to read.

Vertical chart title on page edge (presumably for filing purposes), redundant with horizontal title.

Vertical chart title on page edge (presumably for filing purposes), redundant with horizontal title.

Current insulin rates written vertically in ‘Algorithm for Insulin Adjustments’ table. Vertical chart title on inside page edge.

‘Write BGL in correspond‐ing range box’ written vertically against y‐axis of BGL record.

‘BSL reading (mmol/L)’ is written vertically against y‐axis of BGL record.

Vertical chart title on page edge (presumably for filing purposes).

N/A. Vertical chart title on page edge (presumably for filing purposes).

Missing or ambiguous chart name.

N/A. Title does not specify patient population or insulin route (e.g., adult, intravenous). A heading should be provided for the insulin order record.

Title is presented vertically on inside page edge only, and is not salient. Title does not specify patient population (e.g. adult).

N/A. Title does not specify patient population or insulin route (e.g., adult, subcutaneous) Cue that the chart is for ‘correction doses only’ is not salient.

Title is presented vertically on outside page edge only, and is not salient.

Generic chart title that may be confused with other charts.

Generic chart title that may be confused with other charts. Title is presented vertically on inside page edge only, and is not salient.

22


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Information not displayed in decreasing order of importance. Information presented in top left of a display is more likely to be prioritized as a result of English reading conventions.

‘Important information about IV insulin’ presented after insulin administrat‐ion record, and may not be read first.

BGL and insulin administrat‐ion record are presented after insulin orders. ‘Date’ and ‘time commenced’ is presented after initial data entry (i.e., drug alerts and insulin orders).

BGL and insulin administrat‐ion record are presented after ‘Algorithm for Insulin Adjustments’ table.

Insulin orders are presented after insulin administrat‐ion record (however, arguably this strategy allows insulin administrat‐ion to be presented adjacent to BGL).

BGL and insulin administration records are presented after insulin orders. Routine insulin orders presented on separate chart. Important notes are not grouped.

BGL record is presented after insulin order/ administrat‐ion record. ‘Prescriber Instructions’ are presented after BGL and insulin records and are not salient.

Nurses’ signatures are presented before BGL record and insulin dose. Ad‐hoc use of BGL and insulin administrat‐ion columns.

BGL record is not formally included on the chart.

23


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Elements that ought to be perceptually separated not adequately separated. Avoid unrelated elements being formatted in such a way that they seem to belong together.

Spaces, rather than bold lines, should separate charting record and insulin orders. ‘BGL’ heading should be separated from ‘Time’ heading and row. Location of BGL recording instructions only corresponds to the normal range area.

BGL and insulin administrat‐ion columns should be separated to discourage column shift errors. Unopposed insulin information and ‘Authorisation to Use Guidelines for Adjustments’ should be separated from tables. Information is poorly clustered with dot points.

N/A. Spaces, rather than bold lines, should separate charting record and insulin orders. Distinction should be made between ‘units’ row and ‘initials’ row in ‘Routine Insulin Orders’ table to discourage row shift errors.

BSL and insulin administrat‐ion records should be more clearly separated. Date columns should be separated from one another.

Date rows of insulin administrat‐ion and BGL records should be separated from one another to encourage groupings for each day. Very poor boundaries ‐ excessive use of lines increases visual clutter.

‘Drug Order Record’ should provide lines to write on to discourage row shift errors. Spaces, rather than bold lines, should separate BGL and insulin administrat‐ion records.

Cells for ‘Dose’ and ‘Route’ should be separated from one another.

24


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Labels of the same level of importance formatted differently. Avoid related elements being formatted in such a way that they seem to belong to different categories.

‘BGL’ heading not salient. ‘Important information about IV insulin’ heading is formatted with less importance than all other headings. Inconsistent use of capitalization, colour, and font size across headings of the same importance.

‘BSL’ heading is same sized font as less important labels (e.g. ‘remaining syringe volume’, ‘adjusted by’).Inconsistent use of capitalization across tables. Drug alert table is formatted differently to other tables.

Most headings are inconsistently formatted (including the use of bold, font size, italics, capitalization, and colour). ‘Algorithm for insulin adjustments’ heading is formatted much more prominently than labels associated with BGL and insulin administrat‐ion records. ‘New insulin rate’ heading required to cover old and new rates in algorithm.

‘Year’ subheading is presented using same formatting as chart title. ‘Time given’ in insulin administrat‐ion record is presented using same formatting as ‘Admin‐istration Record’ heading.

‘Admin‐istration of subcutaneous insulin correction doses’ headings is formatted with less importance than ‘BSL record’ heading.

‘Once only Subcutaneous Insulin’ and ‘Telephone Orders’ headings are formatted with less importance than ‘Supplemental Subcutaneous Insulin’ heading, whereby they could be missed. Subheadings of the same importance are inconsistently formatted (e.g. ‘dinner’ and ‘bed‐time’).

Important headings are not written at all (e.g., BSL, dose). Drug Order Record and Administrat‐ion Record headings are presented using the same formatting as Date/ Time/Sign subheading.

Almost all labels are formatted similarly, which could encourage “row shifts”.

25


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Areas for writing too small (cannot accommodate 14 point font). If the space is insufficient for reasonably‐sized handwriting, then this is likely to impact legibility.

Boxes for date, time, BGL record, and nurses’ initials are too small. Use of A4 chart makes content cramped and cluttered.

Boxes for date and time are too small.

Boxes for nurses’ signatures are too small.

Boxes for time, time given, stat/phone insulin orders, and comments are too small.

Boxes for date and signatures are too small.

All boxes that require writing are too small.

Boxes for BSL ‘mmol/L’ units and Insulin ‘units given’ (which need to be written due to the lack of headings) are too small.

All boxes that require writing are too small.

Amount of space devoted to something is excessive. If other chart content is cramped as a result of wasted space, then this could impede readability.

N/A. ADR label is excessive, given that insulin allergies are rare.

N/A. ‘Stat/phone’ orders are excessive (12 rows).

Gap between ‘Correction dose orders’ is excessive.

‘Regular Subcutaneous Insulin’ record is excessive (e.g., a third set of columns).

‘Drug Order Record’ is excessively large.

N/A.

26


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Basic functionality not understandable intuitively (or with minimal explanation) If extensive training is required to understand the basic functionality, then the chart design may be over complex.

There is no clear workflow on the chart.

N/A. BGL and insulin administrat‐ion records are not designed to support use of the algorithm (e.g. ‘BGL change last hr’ could indicate the need for an arrow or an arrow with a record of the insulin change).

Reference to insulin ‘Admin‐istration Record’ on ‘Stat/phone’ orders is not salient and, if missed, could lead to incorrect doses.

Unclear instructions regarding how to administer ‘correction doses’ with respect to other insulin (i.e., whether these doses replace or are in addition to routine insulin).

Unclear whether ‘phone orders’ replace regular and supplemental orders, or are in addition to them. Unclear where to record the ‘reasons for nurse not administering’ codes. Overuse of diagonal lines means that there is not regular form for data entry.

Basic functionality is not clear in regards to diabetic management.

Basic functionality is not clear in regards to diabetic management.

*Based on Gerhardt‐Powals, 1996; Nielsen, 1994; Zhu et al., 2005; Yu et al., 2008.

27

5.2. Cognitive and memory loads Table 4: Usability problems related to cognitive and memory loads, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Information must be transcribed or compared over two pages. If users have to mentally transcribe information from one part of the chart to another, the additional demands on memory may increase user workload and errors.

Queensland Health Guidelines (QH, 2009), and not the chart itself, refer users to ‘Hypoglycae‐mia Management Protocol’ on Queensland Subcutaneous Chart.

Requires user to compare BGL record on front page with ‘Initial Infusion Rate’ formula instructions and ‘Adjustment of Insulin Infusion’ table on reverse page. Also, no support provided for dose calculations.

Requires user to compare first BGL recording on inside pages with ‘Starting insulin rates’ table on outside pages; and to compare BGL recording on inside pages with hypoglycae‐mia management protocols on outside page. Orders need to be written on an IV fluid form.

Requires user to compare BGL record on inside pages with ‘Suggested Initial Stat and Supplemental Insulin Doses’ tables on outside pages; and to refer to outside pages for ‘Hypoglycae‐mia Management Protocol’.

Requires user to compare BGL record on front page with ‘Correction Doses’ on reverse page; and to refer to ‘Inpatient Medication Chart’ for routine insulin prescriptions.

N/A. N/A. Requires user to compare ‘Telephone Orders’ on reverse page with ‘Dose’ on front page.

28


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Information must be compared over different areas of one page. If users have to mentally transcribe information from one part of the chart to another, the additional demands on memory may increase user workload and errors.

Requires user to mentally align current BGL (high to low values, down page) with ‘BGL range’ firstly in the ‘Recommen‐ded Initial Infusion Rates’ (low to high values across page), then ‘Initial Infusion Order’ (low to high ranges, down page).

N/A. Requires user to hold current BGL, current insulin rate and BGL change in last hour (inside right page) in memory and input values into ‘Algorithm for Insulin Adjustments’ table (inside left page) to calculate new insulin rate.

Requires user to mentally align current BGL (high to low BGL values, down the page) with ‘BGL range’ in ‘Supplement‐al Insulin Orders’ (low to high BGL values, down the page).

N/A.

Requires user to add insulin doses over different sections (BGL, supplemental subcutaneous insulin, and then regular subcutaneous orders) of inside pages to determine insulin dose; and to compare separate meal columns across page.

Requires user to compare BSL record on right hand side on page, with BSL ranges prescribed in ‘Drug Order Record’ on left hand side on page.

N/A.

29


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Writing required when chart could provide response options to circle. Should allow the user to rely on recognition rather than recall memory

N/A. N/A. N/A. N/A. Tick‐box format may be more appropriate for ‘Insulin Administration times’, rather than written responses.

Tick‐box format may be more appropriate for Frequency boxes in ‘Regular Subcutaneous Insulin’ table, rather than written responses.

N/A. Route (e.g., SC or IV) could be provided for circling, rather than writing.

*Based on Gerhardt‐Powals, 1996; Nielsen, 1994; Zhu et al., 2005.

30

5.3. Recording of blood glucose levels Table 5: Usability problems related to recording of blood glucose levels, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Information is not displayed as a graph or in a graphlike presentation assuming it was judged that this might reduce errors?

N/A. BGL record could be better displayed as a graph or quasi‐graph.

BGL record could be better displayed as a graph or quasi‐graph.

N/A. BGL record could be better displayed as a graph or quasi‐graph.



BGL record not provided.

Graph looks too small or cramped. Smaller or cramped graphs may be less legible.

Little room for labels and instructions. Columns not wide enough for recordings.

N/A. N/A. N/A. N/A. N/A. N/A. N/A.

31


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Graph label not clear and descriptive. Chart should have a good match between the display of information and the user’s mental model of that information. Unclear labelling may impose additional mental load, which could cause errors or slow evaluation.

‘BGL’ label not salient. ‘BGL’ and ‘Alerts’ labels are presented adjacent to one another even though they correspond to separate axes. Actions to be taken are imbedded with the graph values.

N/A. N/A. BGL’ label not salient. ‘BGL’ and ‘Alerts’ labels are presented adjacent to one another even though they correspond to separate axes.

N/A. N/A. N/A. N/A.

32


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Graph label does not provide example of how data are to be recorded (e.g. numeric value, or ●). Providing an example may reduce the chance of users employing an incorrect format.

Although instructions are provided to ‘write BGL (mmol/L) in correspond‐ing range box’, it may not be clear that only the number should be written, without adding ‘mmol/L’ units.

N/A. N/A. Although instructions are provided to ‘write BGL in correspond‐ing range box’, text is presented vertically and in small font.

N/A. N/A. N/A. N/A.

33


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Vertical axis of a graph not labelled on left and right of page. Placing the BGL values on both sides of the graph may reduce ‘row shift’ (recording or reading data from the row above or below the correct row), and may also aid left‐handed users.

Vertical axis of BGL graph is only labelled on left of page.

N/A. N/A. Vertical axis of BGL graph is only labelled on left of page.

N/A. N/A. N/A. N/A.

34


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Thick vertical lines not placed every 3 to 4 columns of the graph. Placing thick vertical lines every 3 to 4 columns can prevent ‘column shift’, and allow a user to track down a column to the correct row more easily.

No use of thick vertical lines on BGL record.

N/A. N/A. Thick vertical lines are only placed every 7 columns on BGL record.

N/A. N/A. N/A. N/A.

35


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Time and Date boxes too small. Chart should match the user’s task in as natural a way as possible. If the space is insufficient for reasonably‐sized handwriting, then this is likely to impact legibility.

Time and date boxes too narrow to accommodate 14‐point font.

Time and date boxes too narrow to accommodate 14‐point font.

N/A. Time boxes too narrow to accommodate 14‐point font.

Time and date boxes too small to accommodate 14‐point font.

Time and date boxes too small to accommodate 14‐point font.

N/A. Time and date boxes too small to accommodate 14‐point font.


36

5.4. Alerting systems Table 6: Usability problems related to alerting systems (anything that provides cues to the chart user that indicate when something is wrong, such as the notification of abnormal BGLs), rationales for the underlying design rules and specific examples from each Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Fails to include an alerting system where such a system would be of value.

N/A. No use of explicit altering cues, except a minor note to ‘Contact RMO before BSL falling > 4’ and the continual monitoring of BSL and insulin adjustments.

N/A. N/A. N/A. N/A. No use of alerting system.

No use of alerting system (no way to track BGL).

37


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Alerting system fails to make full use of colour to improve its usability. A colour scheme can provide cues to improve the usability of the system (e.g., reducing workload by eliminating the need to actively compare vital signs and criteria).

Although colour is integrated into the altering system, its use is problematic (see Table 10). Colour has not been used to group alerting BGL ranges with correspond‐ing insulin infusion orders.

Alerting system does not use colour.

Although colour has been used to differentiate between parts of the algorithm table, colours do not improve usability. Although red shading has been used in the ‘Hypoglycae‐mic Management’ tables, colour does not relate to BGL alerts.

Although colour is integrated into the altering system, its use is problematic (see Table 10). Colour has not been used to group alerting BGL ranges with correspond‐ing supplemental insulin orders.

Although colour (red) has been used to draw attention to the warnings, there is no direct link to BSL values (that is, the user still has to remember to compare the value to the cut‐off). Also, red font is not salient as it blends in with more trivial information.

Colour has not been used to improve the usability of the alerting system.

N/A. N/A.

38


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Alerting system involves mentally transcribing information between nonadjacent areas of the chart. If users have to mentally transcribe information from one part of the chart to another, the additional demands on memory may increase user workload and errors.

N/A. Alerting scale is on reverse page of BSL record, and is even labelled differently (BGL versus BSL).

BGL change, current BGL, and current insulin rate all have to be mentally transcribed from the left inside page to the ‘Algorithm for Insulin Adjustments’ table to determine insulin change.

N/A. N/A. User required to compare recorded BGL (at the top right of inside page) with information relating to supplemental insulin (at the bottom left of inside page) – nothing prominent to remind user to check supplemental order.

N/A. N/A.

39


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Alerting system fails to allow for modification for individual patients where modifications may be required. Standard clinical threshold scores are not appropriate for all patients.

Although a modifiable target BGL range is provided, it is separated from the BGL record and isn’t salient.

No allowance to modify alerts for individual patients.

N/A. N/A. No allowance to modify alerts for individual patients.

No allowance to modify alerts for individual patients.

N/A. N/A.

40


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Alerting system’s use is less transparent than it could be.

Bottom row of the BGL record is labelled both ‘less than 5 – notify Dr immediately’ and ‘treat hypoglycae‐mia if less than 4’. BGL ranges omit the possibility of a BGL of 5.0 (inconsistent with infusion rate action instructions). Two top rows of the BGL record both require user to ‘notify Dr immediately’ ‐ BGL reading in the 15.1‐20 mmol/L row may imply a less urgent need to call doctor.

No explicit flagging of abnormal BSL in, or near, monitoring record.

Use of the ‘Algorithm for Insulin Adjustments’ table is not intuitive and could be clearer.

N/A. Altering system should signal user in the area for recording BSL itself. BGL times are not arranged in chronological order, increasing the likelihood of a missed BGL reading.

No explicit flagging of abnormal BSL in, or near, monitoring record.

N/A. N/A.

41


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Alerting system fails to include instructions. Unclear instructions may increase ambiguity or user workload, leading to errors.

N/A. N/A. N/A. Fails to refer users to outside pages for ‘Hypoglycae‐mia Management Protocol’. No definition of significant in regards to ‘Significant ketones present’.

N/A. N/A. N/A. N/A.


42

5.5. Action systems Table 7: Usability problems related to action systems (anything that assists the user to take appropriate critical actions, such as the frequency of actions or the integration of a recommended dosage), rationales for design rules and examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Fails to include an action system where such a system would be of value.

N/A. N/A. N/A. N/A. N/A. N/A. No use of action system.

No use of action system.

43


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Action system involves mentally transcribing information between nonadjacent areas of the chart. If users have to mentally transcribe information from one part of the chart to another, the additional demands on memory may increase user workload and errors.

Requires user to mentally align current BGL (high to low BGL values, down the page) with ‘BGL range’ firstly in the ‘Recommen‐ded Initial Infusion Rates’ (low to high BGL values across the page), and then ‘Initial Infusion Order’ (low to high BGL ranges, down the page).

Requires user to compare BGL record on front page with ‘Initial Infusion Rate’ formula instructions and ‘Adjustment of Insulin Infusion’ table on reverse page (no guidance for users to refer to reverse page). Relies on nurses’ initiative to make notification.

Requires user to hold current BGL, current insulin rate and BGL change in last hour (inside right page) in memory and input values into ‘Algorithm for Insulin Adjustments’ table (inside left page) to calculate new insulin rate. Requires user to compare BGL recording on inside pages with hypoglycae‐mia management protocols on outside page.

Requires user to mentally align current BGL (high to low BGL values, down the page) with ‘BGL range’ in ‘Supplemental Insulin Orders’ (low to high BGL values, down the page); and refer to outside pages for ‘Hypoglycae‐mia Management Protocol’.

Requires user to refer to reverse page for hypoglycaemia management guidelines; refer to ‘clinical procedures manual on the internet’ (although a brief guide is provided on chart); to compare BGL record on front page with ‘Correction Doses’ on reverse page; and to refer to ‘Inpatient Medication Chart’ for routine insulin prescriptions.

Requires user to add insulin doses over different sections (current BGL, supplemental subcutaneous insulin, and then regular subcutaneous orders) of the inside pages to determine insulin dose. Requires user to compare two separate meal columns (insulin administrat‐ion and BGL) across page.

N/A.

N/A.

44


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Action system’s use is less transparent than it could be.

Instructions provided, however they are vague or incomplete E.g., “recheck BGL after 15 mins.” – then what?

No heading provided for insulin infusion orders. Some vague instructions E.g. ‘seek advice if regime is failing to control patient’s BSL. ’

Instructions provided, however they are vague or incomplete E.g., ‘Aim for BGL 4.0 to 8.0 mmol/l”. Does this mean that nurses are expected to ignore/ override the algorithm if it is failing to deliver a BGL in this range? If so, when should they take action and what action should this be? No ability for the user to record calculations. Requires nurses to determine doses (10 fold range).

Instructions could be better grouped together. Admini‐stration of supplemental insulin is not intuitive.

Inconsistent instructions. E.g., trigger for hypoglycaemia on BSL record is <4, compared to <3 in instructions. Ambiguous terminology. E.g., ‘a meal, 2‐4 dry biscuits etc’, ‘notify RMO urgently (MET call’). Unclear instructions describing hypoglycae‐mia management.

Instructions provided, however they are vague or incomplete, e.g., protocol when waiting for MET teams to arrive (‘recheck BGL hourly until stable’, without defining ‘stable’). Correct use of supplemental insulin is not transparent. Unclear where the codes for non‐administrat‐ion should be recorded.

N/A. N/A.

45


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Action system fails to include instructions. Unclear instructions may increase ambiguity or user workload, leading to errors.

Queensland Health Guidelines (QH, 2009), and not the chart itself, refer users to ‘Hypoglycae‐mia Management Protocol’ on Queensland Subcutaneous Chart. There are no clear instructions on how to use the chart or how to adjust doses.

N/A. Although instructions are included, they are not inclusive of all actions required.

N/A. Although some instructions are provided, they are unclear (especially related to correction doses).

Guidelines refer users to ‘Hypoglycae‐mia Management Policy’.

N/A. N/A.


46

5.6. Language and labelling Table 8: Usability problems related to language and labelling, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Grammatical errors. Words, phrases, and concepts used should be familiar to users. Any opportunity for ambiguity or misinterp‐retation should be avoided to minimize errors.

Several sentences are under‐punctuated. Use of the abbreviation ‘Dr’ when not prefacing a surname.

Misplaced period in ‘...Glucose at 60 – 80 mL/hour. (prescribed on IV fluid chart).’ Missing period in ‘(…TPN therapy)’. Missing ‘as’ in ‘Insulin Infusion’ guidelines and ‘then per routine monitoring’. Use of ‘i.e.’ instead of ‘e.g.’

Several sentences are under‐punctuated. Use of terms ’15 minutely’ and ‘blood or urine ketones are to be done if…’ Several suggested units missing spaces between the value and unit. ‘Current BGL’ table headings appear to have spaces between individual letters.

Use of commas to divide what should be separate sentences. Use of the abbreviation ‘Dr’ when not prefacing a surname.

Odd use of commas in the ‘Management of hypoglycae‐mia’ section. Inconsistent use of full stops.

N/A. N/A. N/A.

47


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Expressions or instructions less clear and/or more jargonistic than they could be.

BGL ranges omit the possibility of a BGL of 5.0 (inconsistent with infusion rate action instructions). No labels are provided in ‘Recommen‐ded Initial Infusion Rates’ table. Instruction box is unclear and hard to find.

Several vague instructions. E.g., ‘seek advice if regime is failing to control patient’s BSL. ’ Use of the terms ‘nocte’ and ‘unopposed insulin administration’.

Several vague instructions. E.g., what constitutes ‘persistent’ hypoglycaemia, ‘nil by mouth’, and ‘minor vs. severe symptoms of hypoglycae‐mia’ Sentence with three conditions at bottom of inside left page is complicated.

Several vague instructions. E.g., reference to ‘significant ketones’, which is undefined. Use of ‘At 02:00hrs’ in ‘Monitoring Instructions’ could be interpreted as 2:00am or every 2 hours.

Several vague instructions. E.g., ‘check for cause of hypoglycae‐mia’ without guidance. Nothing to prevent clinicians from adding a symbol for ‘units’. No differentiat‐ion between BGL readings at ‘random’ and ‘other times’.

Several vague instructions. E.g., ‘if repeated hypoglycae‐mia…’ No indication where oblique lines should be drawn when discontinuing insulin orders. ‘Sliding scale’ referred to without definition.

N/A. N/A.

48


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Abbreviations or acronyms used unnecessarily (assuming they may be less transparent than not using the abbreviation or acronym).

TPN, HHS, I. TPN URMN, DM, PHARM, tds. Use of the symbols ‘<’ and ‘>’. Chart design may encourage users to include unit abbreviations (e.g. ‘U’).

ALS, MET, s/c, HHS, MRN. Use of the symbols ‘<’ and ‘>’. Chart design may encourage users to include unit abbreviations (e.g. ‘U’).

TPN, HHS, I, IPBS, T2DM. Use of the symbols ‘<’ and ‘>’. Use of circled letters A, B and C in instructions, ‐ instead of (A), (B) and (C) ‐ is odd (as circled C is the copyright symbol).

UR, QID, REL, TDDI. Chart design may encourage users to include unit abbreviations (e.g. ‘U’). Inconsistent use of ‘BGL’ and ‘BSL’ across chart.

CHO, ALS, IM, AC, PC. Use of the symbols ‘<’ and ‘>’. Use of up and down arrows in BGL record. Use of circled letters as codes for non‐administrat‐ion of insulin.

SAO2. Chart design may encourage users to include unit abbreviations (e.g. ‘U’).

DOB, ADR, UR, PRN, PCA, NI, SR. Chart design may encourage users to include unit abbreviations (e.g. ‘U’).

Position of clinicians’ initials required for authorisation could cause confusion with close abbreviations or acronyms.

N/A. Initials could be confused with ‘remaining syringe volume’ values.

N/A. Initials could be confused with dose in ‘Routine Insulin Orders’.

Initials could be confused with dose in ‘Correction Doses’ (at the very minimum, diagonal lines could increase clutter).

Initials and signatures could be confused with dose in ‘Regular Subcutaneous Insulin’ and ‘Supplement‐al Subcutaneous Insulin’.

Initials could be confused with dose or BGL values (depending on what is recorded adjacent to initial column), especially given the identical formatting.

Route abbreviat‐ions, initials and times could be confused with dose (especially if prescriber’s initials were ‘SC’ or ‘IV’).


49

5.7. Font Table 9: Usability problems related to the use of fonts, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Font appears compressed Compressed fonts slow reading.

‘Alerts’ and ‘Important information’ fonts are somewhat compressed.

N/A. N/A. N/A. N/A. N/A. N/A. Compressed fonts used throughout chart.

Text too small (less than 11 point font). 10 point font may be less legible.

Font size 9‐10 is used throughout the chart.

Font size 9‐10 is used throughout the chart, and size 7 for certain labels (e.g. ‘adjusted by’).

Font size 9‐10 is used throughout the chart, and size 7 within ‘Algorithm for Insulin Adjustments’ table.

Font size 8 is used on the outside pages, and size 6‐7 is used for certain labels on the inside pages (e.g. ‘units’, ‘initials’). Guidelines are too small and tightly packed.

Several items use very small fonts (e.g., notes concerning high and low BSL, and area to print doctor surname for dosage information).

Font size 9‐10 used for non‐heading terms. Several items use very small fonts (e.g., in the ‘Supplement‐al Insulin’ order and ‘regular insulin’ record).

Font sizes 9 and 10 are used throughout the chart.

Non‐heading font size 6‐7 is used, and size 4‐5 for legends on the inside pages (centre).

50


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Text size misleading (e.g., important information very small and vice versa). Chart should have a good match between display of information and user’s mental model of that information to prevent misinter‐pretation.

Instructions in ‘Important information about IV insulin’ are in small font.

‘BSL’ heading is the same sized font as less important labels (e.g. ‘remaining syringe volume’, ‘adjusted by’). Overuse of bold and/or italic font throughout chart.

‘Current BGL’ heading is the same small sized font as all other (less important) labels in charting record. Large font used in ‘Algorithm for Insulin Adjustments’ table draws user’s attention. Bolded instructions increase reading difficulty.

Size of fonts used for labels in the monitoring and administration sections is inconsistent, e.g. ‘Time Given’ is in the same large bold font as the sub‐heading it falls under (‘Administration Record’).

BSL alerts are too small The Routine Insulin and Stat Dose notes could be much more prominent given their importance.

Small fonts used in Supplemental Subcutaneous Insulin’ order record and ‘regular subcutaneous insulin’ records might imply that this information is less important than terms in larger font (e.g. meals).

N/A. ‘Reason for nurse not administer‐ing’ key is presumably important – and yet is virtually unreadable due to small font. Regular medications do not get the same bold all‐cap title as do “Once Only” and “Telephone” medications.

51


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Capitalization used too often. Upper‐case text should not be over‐used as it attracts attention but is slower to read than mixed‐case text.

Capitalization is used for headings of little importance (e.g. ‘Date/Start Time’), but not for headings of high importance (e.g. ‘Important Information).

Most headings and table labels use capitalization – not used effectively to draw attention to important information. Headings should be title case.

Capitalization is used too often in ‘Algorithm for Insulin Adjustments’ table.

Inconsistent use of capitalization on front page ‐ one major heading is capitalized, and the other is not.

Inconsistent use of capitalization on headings (e.g. insulin administrat‐ion should be in capital letters) Unnecessary use of capitalization in patient identification area.

N/A. Capitalization is used for all pre‐printed column headings.

Capitalization used throughout for some headings e.g. “AFFIX PATIENT ID LABEL HERE”.

*Based on Gerhardt‐Powals, 1996; Nielsen, 1994; Zhu et al., 2005; Frascara, 2005; Lorch Jr. et al., 1995; Bernard et al., 2003; Pelli et al., 2007.

52

5.8. Colour Table 10: Usability problems related to the use of colour, rationales for the underlying design rules and specific examples from each chart Usability problem Rationale*

Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



No colour, or colour present in a non meaningful way. Colour can provide useful cues aiding chart interpret‐ation.

Although colour is used in the alerting system, it could be implemented better (see below).

No use of colour.

Although colour is used to differentiate parts of the algorithm table, colours do not improve usability. Red shading used in ‘Hypoglycae‐mic Management’ tables does not relate to BGL alerts.

Although colour is used in the alerting system, it could be implemented better (see below).

Although red text has been used as an alerting tool, it is not salient. Red text also used for generic instructions.

Although colour is used in the ‘instructions for using medication chart’ section, colours do not improve usability.

No use of colour.

Although colour is used, it doesn’t improve usability related to diabetic management.

53


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



Colour shades used are inappropriate. Light coloured backgrounds ensure that observations written on top are easily visible.

While BGL record colour shades are appropriately pastel, the different bands of colour are difficult to differentiate (especially in low light). No clear progression of intensity.

N/A. Use of white font on coloured background in the ‘Algorithm for Insulin Adjustments’ and ‘Hypogly‐caemic Management’ tables are difficult to read, especially under low light. Use of red is inconsistent between warnings and ‘Algorithm for Insulin Adjustments’.

While BGL record colour shades are appropriately pastel, the different bands of colour are difficult to differentiate (especially in low light). No clear progression of intensity.

Red used to code multiple points of varying importance. Blue shading of alternate columns precludes the use of colour for indicating abnormal‐ities.

N/A. N/A. N/A.

54


Queensland IV Chart

Fremantle IV Chart

Sydney IV Chart

Queensland SC Chart

Tasmania SC Chart

Sydney SC Chart



One or more colours could be deceptive. Colours that are intuitively inconsistent with what they are signalling (e.g., red indicating non‐critical information) could induce errors.

Odd use of grey shading in BGL record row to alert chart user to abnormal BGLs.

N/A. Colours are not used to indicate meaning; only used for separation of information. Green shading used in the ‘Current Insulin Rate 0.1‐1.9 units/hr’ row may imply that particular range of insulin is good.

Odd use of grey shading in BGL record row to alert chart user to abnormal BGLs.

Red used for instructions on completing the form

N/A. N/A. N/A.


6. Usability Issues and Potential Design Solutions In this section, we bring together the outcomes from the previous sections and outline potential solutions to the usability issues identified. All seven evaluators independently identified the Queensland subcutaneous and intravenous insulin charts as representing best practice out of the charts we reviewed. However we nonetheless identified a number of usability issues with even these two preferred charts that could potentially be addressed by a re‐design. Hence we propose that two new insulin charts should be developed, but that the Queensland charts could be used as the starting point for these new charts. While developing final working versions of these new insulin charts was outside of the brief of the present project (the development of new insulin chart designs has been integrated into the proposed follow up project, as detailed in section 7), we have provided a number of potential design solutions below that could be used in these new charts. We have divided our suggestions for potential design solutions into the three main functions of insulin charts (monitoring of blood glucose levels, administration of insulin, and prescription of insulin), in addition to general presentation considerations. It is important to note that because insulin charts are attempting to perform more than one function, the optimal design solution for one particular function may conflict with the optimal design solution for another function. This has led to some competing design solutions, where it may turn out to be impossible to accommodate both solutions on the same form, and hence a compromise will be necessary (where this happens below, explanatory notes are provided). Also note that the figures in this section are for illustrative purposes only and are not intended to reflect a complete design solution. 6.1. Monitoring of blood glucose levels

6.1.1. Displays of blood glucose Insulin charts differ in the way in which blood glucose levels are presented. Charts can display patients’ blood glucose levels in the form of ‘drawn dot’ graphs, standard tables (with BGL readings recorded across rows or down columns), or as ‘quasi‐graphs’ presented as tables with BGL range rows (source: task analysis preliminary descriptions, see Table 11, Appendix B). The task analysis interviews suggested that many clinicians find graphical displays of blood glucose levels inappropriate because they do not have a fixed time‐axis. For instance, from the perspective of a busy clinician who fails to closely examine the time‐axis, a trend line of five BGL readings taken at 15‐minute intervals (i.e., over a 75 minute period) could be interpreted and acted upon in the same way as an adjacent trend line of five BGL readings taken at 2‐hour intervals (i.e., over a 10 hour period). Trend lines, invariably drawn straight from one BGL recording to the next, can also encourage misinterpretation among chart users (source: task analysis interviews with clinicians). Often, junior medical officers and nurses incorrectly infer direct linear increases and decreases in blood glucose levels between recordings; an inference that can lead to clinically inappropriate actions, especially when the time between readings is protracted (e.g., four or more hours). Despite a general preference for blood glucose levels to be presented numerically across

56

rows or down columns, endocrinologists do acknowledge (source: task analysis interviews with clinicians) that non‐experts typically prefer graphical BGL records, as they provide a visual representation of the physiological trend. Potential design solution The problem with presenting blood glucose level numerically in a single row or column is that our previous research indicates that this strategy led to a dramatically high proportion of errors when experienced health professionals were attempting to identify physiological parameters outside of the normal range in a patient observation chart (Horswill et al., 2010). When the same data was presented in a graphical form, about a third fewer errors were made. However, the insulin charts differ from the general observation chart in two ways: (1) as noted above, the time increments may vary, making graphical trends potentially hard to interpret and (2) only one physiological parameter, blood glucose level, is being recorded (compared with multiple parameters on a general observation chart). With only one parameter to attend to, it could be that it is less important to de‐clutter the presentation of the data to the extent possible with a graph (where the graph may flag misleading trends). That is, the human factors advantages of using a graph may be less apparent with insulin charts. On the other hand, presenting the data as a row of numbers was problematic. While it is possible that very experienced users, such as endocrinologists, may have the expertise to immediately detect any problems with blood glucose level when the data is presented in this form, the data also needs to be interpreted by less experienced users, where additional cues may be useful to signal problematic readings. All the evaluators favoured the “quasi‐graph” approach used in the Queensland charts as a compromise design solution. This approach involved presenting BGL readings as numerical values in a table of BGL range rows (e.g., 4.0 ‐ 8.0 mmol/L, 8.1‐ 12.0 mmol/L) (see Figure 1). It is possible that the recording of numerical values (compared to ‘drawn dots’ in a true‐graph) will encourage chart users to more closely examine the relationship between BGL readings within a trend line, and between BGL readings and the time‐axis. The quasi‐graph also precludes non‐experts from having to mentally visualize increasing and decreasing blood glucose levels (as required by BGL records of written numbers presented across a row or down a column), whilst discouraging the assumption of linearity between adjacent readings (compared to ‘drawn dots’ in a traditional graph). If an insulin chart utilizes a quasi‐graph to display blood glucose levels, then there are a number of strategies that could aid users. First, we suggest that scales should be included on the left and right of the graph (the failure to do so was a common usability problem identified in the heuristic analysis). This arrangement is thought to reduce row‐shift errors (i.e., users accidentally jumping into the wrong row when recording or reading data), and help left‐handed chart users who may cover the right‐hand‐side scale with their left hand when writing (Preece et al., 2009). This is also an important consideration for those charts that present BGL records across an A3 sized page, in landscape orientation. If users are required to write on the chart when bound in a patient’s folder by the left edge of the page, nurses have been observed to typically push

57

the right hand side of the chart to the left so that the right side folds over the margin crease, obscuring the scales on the left of the graph. Second, within the scales, we suggest that values should be aligned to be as close to the columns for recording observations as possible (i.e., right‐aligned in the left‐hand‐side scale and left‐aligned in the right‐hand‐side scale) (see Figure 1). In addition, we suggest that every third column should be denoted by a thicker vertical line to reduce column‐shift errors (i.e., users accidentally jumping into the wrong column when recording or reading data) (Preece et al., 2009) (see Figure 1). This makes the borders of adjacent columns look different to one another (they will either have a bold line to the right, to the left, or have no bold line divider), which should make them harder to confuse.

Blood Glucose Level RecordWrite BGL (mmol/L) in corresponding range box

Date Date

Time Time

> 20.0 > 20.0

16.1 - 20.0 16.1 - 20.0

12.1 - 16.0 12.1 - 16.0

8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0

< 4 < 4

Figure 1: Example of a BGL record displayed as a quasigraph. Scales are presented on the left and right; bold vertical lines are placed every three time columns; rightaligned values in the lefthandside scale; leftaligned in the righthandside scale; values formatted the same as one another; and values formatted differently from the variable label. Note: The illustrative figures in this section are only intended to demonstrate the specified design element(s), and are not presented as part of a complete design solution for insulin charts. Please disregard all design elements not mentioned in the captions accompanying each figure. Although most insulin charts instruct users to record blood glucose levels to one decimal place, some clinicians question whether users should instead round to the nearest whole mmol/L, given that insulin is ordered against whole numbers of blood glucose and that clinically relevant differences are only meaningful at the whole number level (source: task analysis interviews with clinicians). Similarly, the precision of blood glucose monitoring equipment also needs consideration. The product information

58

manual of a typical blood glucose monitoring device in regular hospital use reported the precision of test strips (n= 5184), tested at different glucose concentrations, worsens with higher BGL concentrations (e.g., M = 2.4 mmol/L, SD = 0.13 mmol/L; M = 10.8 mmol/L, SD = 0.34 mmol/L; M = 21.1 mmol/L, SD = 0.76 mmol/L) (Optimum Omega, 2007). These findings suggest that a BGL reading above 10 should be rounded to the nearest whole mmol/L, and that a reading above 2 should be rounded to the nearest 0.5 mmol/L. There are competing human factors considerations on whether blood glucose level should be recorded to one decimal point or rounded to the nearest whole number. On the one hand, the use of decimal places introduces extra visual clutter and it likely to reduce the legibility of handwritten numbers. Also, one is introducing unnecessary additional information into the display, which may compete for the user’s attention with the information that does matter (i.e., the whole number). On the other hand, if there is a requirement for the user to record whole numbers only, one is forcing them to perform the extra mental transformation of rounding (assuming the BGL monitoring device provides a reading to one decimal place). This may introduce additional scope for errors under pressure). It is not clear which strategy is likely to lead to the fewest errors. We suggest that this dilemma should be addressed empirically, by running behavioural experiments comparing the two options to determine which actually leads to the fewest errors.

6.1.2. Blood glucose alerting systems We found that insulin charts varied considerably in the way that abnormal blood glucose levels were signalled to users. Although a small number of charts employed single parameter track and trigger systems, most charts only provide target BGL ranges or provide no guidelines at all (source: task analysis systematic descriptions, see Table 12, Appendix B). The most rudimentary alerting systems either incorporate target blood glucose ranges into a chart’s instructions or protocol, or adjacent to the blood glucose record (source: heuristic analysis). The problem with this approach from a human factors perspective is that it requires the user to perform a comparison, involving mentally transcribing information from one part of the chart (BGL observations) to another (prescribed cut‐off ranges). Observation charts that used this approach yielded high error rates in our previous research (Horswill et al., 2010). All the evaluators much preferred the single parameter track and trigger systems used in the Queensland charts. These are early warning systems that use the routine observation of blood glucose levels (the ‘tracking’) in tandem with established criteria (the ‘triggers’) to prompt standard responses to deteriorating patients. For example, if the BGL of a patient receiving subcutaneous insulin fell below 4 mmol/L, then the chart would prompt the user to record this value in a range with a certain background colour. That is, the user does not have to look up the cut offs: they just have to notice whenever a value is recorded in a coloured range, which is far less demanding. Even when a single parameter track and trigger system was used, we found that many insulin charts did not implement them in the most effective way. For example, we found that some colour cues may not have been salient enough to effectively draw a user’s

59

attention. Even in cases where colour cues were more overt, the shaded gradients between different ‘triggers’ could be difficult for users to differentiate (especially for colour blind‐users) (source: heuristic analysis). Potential design solution If an insulin chart utilizes a quasi‐graph (as suggested in 6.1.1.), we suggest that a single parameter colour coded track and trigger system is likely to facilitate the detection of abnormal blood glucose levels (see Figure 2). This suggestion is consistent with recent experimental evidence indicating that users take significantly less time to recognise that a patient is deteriorating on charts with colour coded altering systems, compared to those without (Christofidis et al., in preparation). We suggest that the system should utilise an intuitive colour progression (e.g., where an observation in a white row indicates a normal BGL and an observation in a red row indicates a severely abnormal BGL), and colour density progression (i.e., denser colours signal progressively more serious abnormalities) to facilitate interpretation by colour‐blind users. We also suggest that the row corresponding to a hypoglycaemic event (i.e., BGL less than 4 mmol/L) be shaded with a different colour to those rows that correspond to hyperglycaemic events (i.e., BGL greater than 12 mmol/L), as it triggers a different treatment process (see Figure 2). We suggest that, ideally, the track and trigger system should only use five colours or fewer (including white space) to avoid the chart looking overly cluttered (Preece et al., 2009).


Date Date

Time Time

Notify Doctor immediately > 20.0 > 20.0 Notify Doctor immediately

Notify Doctor if 2 consecutive BGLs > 16 16.1 - 20.0 16.1 - 20.0 Notify Doctor if 2

consecutive BGLs > 16



8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0

Treat hypoglycemia and notify Doctor immediately < 4 < 4 Treat hypoglycemia and

notify Doctor immediately Figure 2: Example of a BGL record with a single parameter colour coded track and trigger system, with intuitive colour and density progression.

6.1.3 Frequency of blood glucose monitoring Implementing insulin therapy in a hospital setting requires frequent and accurate monitoring of blood glucose levels. Given that no empirical investigation testing the effect of frequency of blood glucose monitoring on the incidence of hyperglycaemia or hypoglycaemia has been conducted (Clement et al., 2004), existing guidelines are limited to expert and consensus opinion. Typical recommended testing frequencies during subcutaneous therapy include at pre‐meals and bedtime for patients who are eating (or every four to six hours for patients who are not eating) and hourly for patients who are subject to continuous intravenous insulin until their blood glucose levels are stable (and then every two hours) (Clement et al., 2004).

60

Despite these recommendations, and perhaps in light of the limited empirical evidence to support them, we found that the reviewed insulin charts varied widely in how frequencies of monitoring blood glucose levels are indicated. Some charts provided users with instructions and some provided tick‐box options that could be selected (e.g., hourly or two hourly). However, other charts enforced a rigid schedule (e.g., columns or rows corresponding to before and after meals) or provided no frequency indicators, leaving monitoring frequency open to individual clinical judgment (source: task analysis systematic descriptions, see Table 15, Appendix B). We felt that, on subcutaneous charts, tick‐box options (compared with fixed meal‐based columns or rows) could be advantageous as they allow for some flexibility and modification (i.e., medical officers can choose from several options or elect their own monitoring frequency, and adjust as necessary). Indeed, those charts with fixed meal‐based columns or rows required additional columns or rows to accommodate extra blood glucose readings. The placement of these additional columns or rows, relative to meal‐based records (see Figure 24 and Figure 25, Appendix C), can make it difficult for users to follow chronological changes in BGL because they mean that BGL data would be unlikely to appear in chronological order on the form. In addition, it becomes more difficult to align (especially retrospectively) the results of these extra BGL tests with corresponding insulin orders and administration (source: heuristic analysis). However, those charts that used tick‐boxes to indicate BGL monitoring frequency were not without problems. Some tick boxes were not displayed in a salient way (i.e., easy to overlook) and/or were ambiguously labelled (source: heuristic analysis). This could potentially lead to users monitoring blood glucose levels at the wrong frequency: either too often (causing discomfort to patients) or not often enough (increasing the likelihood of unnoticed hyper‐ or hypoglycaemia). This is where it could be argued that the forcing‐function of a meal‐based record (possibly making BGL readings less likely to be missed because they are always attached to routine events) might be preferable. Potential design solution Assuming the guidelines themselves have some clinical validity, we suggest that overall the tick‐box options to indicate BGL monitoring frequency are likely to be preferable from a human factors perspective. We would argue that the potential for error that can result from the non‐chronological placement of extra BGL test records required by meal‐based BGL monitoring displays far outweighs the potential for error that can result from an unnoticed tick‐box (where steps can be taken to design the tick boxes so they are less likely to be missed). In terms of where these tick boxes should be placed, we suggest that, given recording (or checking) BGL monitoring frequencies is one of a chart user’s first tasks, BGL monitoring frequency instructions are placed towards the top left of a chart’s page, as information presented in top left of a display is more likely to be prioritized as a result of English reading conventions (Preece et al., 2009). For intravenous insulin therapy, we suggest that a single set of tick‐boxes (e.g., with ‘hourly’ and ‘two hourly’ options) is the best option given that monitoring frequency does not tend to vary much for these patients.

61

For subcutaneous insulin charts, one possible design solution is to integrate BGL monitoring tick boxes into each date column of the BGL record (see Figure 3) to ensure that tick‐boxes are appropriately flexible and also salient enough to consistently draw users’ attention. This makes tick boxes more difficult to ignore when BGL data are entered onto the form, encouraging users to prescribe and check the BGL monitoring instructions as they start each new day of observations.


Date Date

BGL Monitoring

Instructions

[ ] Standard (Pre-meals and at 21:00) [ ] Standard (Pre-

meals and at 21:00) [ ] Standard (Pre-meals and at 21:00)

BGL Monitoring Instructions

[ ] At 02:00 [ ] At 02:00 [ ] At 02:00

[ ] 2 hours post-meal [ ] 2 hours post-meal [ ] 2 hours post-meal

[ ] Other: ________________ [ ] Other:

________________ [ ] Other: ________________

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0


notify Doctor immediately Figure 3: Example of a BGL record with BGL monitoring tickboxes provided for each day.

Some hospital wards employ time plans (e.g., a laminated poster at a nurse’s station) as an adjunct tool to guide the frequency with which blood glucose levels are monitored. Although beyond the scope of this project, we have concerns that this particular practice could lead to a greater likelihood that a scheduled BGL reading is missed. Often these time plans only cover several hours, rather than a full 24‐hour day. Thus when the time plan is erased to document a new BGL monitoring schedule, the user either has to rely on their memory of when previous (and multiple) blood glucose levels were taken, or has to refer to each patient’s chart separately (source: task analysis). Both of these factors could lead to increased errors.

6.2. Administration of insulin

6.2.1. Delayed subcutaneous insulin administration Although subcutaneous insulin should ideally be administered with food and within a 15‐30 minute window after a BGL reading has been taken, in reality there are often significant differences between the monitoring of patients’ blood glucose levels and the subsequent administration of meal time insulin (source: task analysis). This delay is often due to practical constraints. For example, nurses typically measure and record their patients’ blood glucose levels, one after the other, as a grouped task. They then must wait for their patients’ meals to arrive before they administer insulin. Thus the time between blood glucose readings and insulin administration (which should be 30 minutes maximum) is dependent on when a patient’s meal arrives (source: task analysis). In one particular instance (source: task analysis), it was reported that nurses on both first

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floor and fifth floor wards recorded their patients’ blood glucose levels between 6:30am and 7:00am. However patients on the fifth floor received their breakfast at 7:00am, whilst patients on the first floor waited until 8:30am (where insulin was administered with this meal). This is a potential problem as patients’ blood glucose levels, and thus their insulin requirements, could change substantially over this time period. While the cause of these delays is not a chart design issue, in many of the insulin charts reviewed (source: task analysis systematic descriptions, see Table 16, Appendix B), the insulin administration record was not linked to the corresponding BGL reading. For example, in some charts, users were required to document a BGL reading at a certain time point in one table and then document the corresponding administered insulin dose at the same time point in another table. Depending on the chart, these separated records could be presented as adjacent tables on the same page, on separate pages of the same chart, or on separate charts altogether. We argue that the separation of BGL and insulin administration is a human factors problem, as it may give the impression to the non‐expert that it is not critical for insulin administration to directly follow a BGL reading (hence implicitly encouraging lengthier delays between the two). It also could be a problem if the magnitude of the BGL reading itself is supposed to influence the insulin dose (where any required adjustment to insulin dose as a result of BGL may be less likely to be noticed if the two are separated). This separation might be a particular problem in situations where readings of patients’ blood glucose levels and subsequent insulin administrations are not performed by the same nurse (e.g., during morning ward rounds where a nurse on night duty will measure and record a patient’s BGL, but a nurse on day duty will administer and record the corresponding insulin) (source: task analysis observations). Potential design solution One design solution to this issue, used in several of the reviewed charts, was to record BGL reading and subsequent insulin administration dose in the same time column or row, hence visually linking the two (see Figure 4 below). As the user naturally scans from the top to the bottom of the chart, we argue that this layout will cue users to administer insulin after recording a BGL reading. The aligned display will also reduce users’ cognitive load by eliminating the need for comparisons across visually separated areas of the chart. We suggest that this type of format should also be used for intravenous infusion charts in order to discourage delayed adjustments to an insulin infusion rate after BGL readings have been recorded.

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Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0


notify Doctor immediately

Insulin Administration

Blood Glucose Level Record


Figure 4: Example of an insulin administration record aligned directly below a BGL record.

6.2.2. Administering an incorrect subcutaneous dose To determine whether a supplemental insulin dose is necessary (and, if so, what amount), subcutaneous charts require users to (whist holding the routine insulin order dose in mind), compare a patient’s current BGL reading with the BGL ranges prescribed in the supplemental insulin order. (Alternatively, they could in principle ascertain the supplemental dose first and hold it in mind while reading the routine dose.) Users then need to mentally sum the routine and supplemental insulin values, and document the total dose in the insulin administration record, completing a process that requires a visual cross‐comparison between up to four different sections of the chart (source: heuristic analysis). In some cases, users are required to compare these sections over two separate charts (source: task analysis systematic descriptions, see Table 19, Appendix B). For example, on a subcutaneous chart evaluated in the heuristic analysis, routine insulin administration is recorded on a separate chart to supplemental insulin administration and BGL records (see Figure 24, Appendix C). We argue that the more these areas are separated from one another, the more difficult comparisons are to make, and the more likely a chart user will administer an incorrect insulin dose. Potential design solution We suggest that, at the very least, routine and supplemental insulin orders ought to be presented on the same page as the BGL and insulin administration records to reduce cognitive load (to avoid the user having to hold a blood glucose level reading in memory, while turning the page or referring to another chart to determine the appropriate insulin dose). However, even with all the information available on the same page, determining the correct insulin dose can still be a challenging task for a clinician working under pressure in a highly distracting environment. Errors are reported to be commonplace (source: task analysis), to the point where many hospitals require this step to be double‐checked by a second clinician. One potential design solution to make this task easier could be to

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take advantage of the quasi‐graph presentation advocated earlier to display BGL data (see section 6.1.1.). If a quasi‐graph is used then it may be possible to align the row ranges of the BGL record with the corresponding row ranges of the supplemental insulin order, as illustrated in Figure 5 below. This design solution prevents users having to cross‐compare a patient’s BGL reading with a separate table of BGL ranges across different areas of the page; instead users can visually scan across the relevant BGL range row to reach the appropriate supplemental dose. Note that, in the illustration in Figure 5, we have deliberately removed the supplemental insulin cells corresponding to low BGL ranges (where supplemental insulin should never be given), as the mere presence of the cells may encourage clinically inappropriate prescriptions. Similarly, if an insulin chart utilizes a single parameter colour‐coded track and trigger system (as recommended in section 6.1.2.), the supplemental insulin order could also incorporate the colour‐code (as shown in Figure 5 below) to provide an additional cue to users that insulin requires administering and also to reduce the likelihood of row shift errors (users accidentally reading off the prescribed dose from the wrong row).

Blood Glucose Level Record Supplemental Insulin OrdersWrite BGL (mmol/L) in corresponding range box

Date Date Start date

Time Time / / / / /

Notify Doctor immediately > 20.0 > 20.0

Notify Doctor if 2 consecutive BGLs > 16 16.1 - 20.0 16.1 - 20.0


8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0

Treat hypoglycemia and notify Doctor immediately < 4 < 4


SupplementalInsulinOrders

Figure 5: Example of a BGL record’s colour coded range rows aligned with the corresponding colour coded blood glucose range rows of a supplemental insulin order record. One potential design solution, that may help reduce the likelihood of users making an error when summing the routine and supplemental insulin dose, is to require them to record both the routine and supplemental dose to be administered (i.e., this information should be transcribed across from the insulin order sections). These doses could be recorded in separate rows but in the time column as the relevant BGL (as illustrated in Figure 6).

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Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0



Routine Insulin Administration

Supplemental Insulin Administration


Routine Insulin Administration

Supplemental Insulin Administration

Figure 6: Example of a supplemental insulin administration record presented immediately beneath a routine insulin administration record, with aligned date and time columns. The aim of this design solution is to avoid users having to hold routine and supplemental insulin doses in memory while summing them, and will also help users who need to retrospectively examine patients’ insulin administrations (e.g., users can simply refer to the grouped insulin administration record to determine how much routine and supplemental insulin was administered, rather than having to engage in ad‐hoc interpretations of insulin orders). Of course, one disadvantage of this solution is that the user has to record more information in the form than previously but this might be a worthwhile cost if it was found to improve the likelihood of the patient receiving the correct dose. If this design solution is adopted, then we suggest that the routine insulin administration record be presented above the supplemental insulin administration (see Figure 6 above) to discourage a sliding scale approach (i.e., when supplemental insulin is administered in isolation, and not in addition to routine insulin), as the user naturally moves from the top to the bottom of the chart (i.e., they would visually encounter the routine insulin cells first).

6.2.3. Supplemental insulin as a sliding scale To further discourage a sliding scale approach, the general proximity of supplemental insulin orders relative to routine insulin orders also needs consideration. Because supplemental insulin is not necessary for all patients or at all times, some clinicians have begun to question whether the position of supplemental insulin orders on a chart encourages hospital staff to adopt a sliding scale approach (source: task analysis). Some charts, for example, require users to refer to a separate chart to record routine insulin orders (see Figure 24, Appendix C). In this instance, Medical Officers are required to prescribe routine insulin on one chart and prescribe supplemental insulin and record blood glucose levels on a separate chart, increasing the likelihood that the routine doses will be forgotten altogether.

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Potential design solution To discourage the overuse of supplemental insulin orders, we suggest that subcutaneous insulin charts ought to position routine insulin orders in a way that leads chart users to naturally prioritize routine over supplemental insulin orders. For example, routine insulin orders could be placed to the left of, or above, supplemental insulin orders (see Figures 7 and 8 below respectively), as information presented in the left, or towards the top, of a display is normally attended to first (Preece et al., 2009).

Routine Insulin Orders Supplemental Insulin Orders

Routine Insulin Orders Supplemental Insulin Orders


Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0




Figure 7: Example of a supplemental insulin order record presented to the right of a routine insulin order record.

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Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0



Routine Insulin Orders

Breakfast Breakfast Breakfast

Lunch Lunch Lunch

Dinner Dinner Dinner

Pre-bed Pre-bed Pre-bed

Supplemental Insulin Orders




Figure 8: Example of supplemental insulin orders presented below routine insulin orders. One problem with this design solution is that it is not commensurate with the design solution suggested in section 6.2.2. (see Figure 5), where we suggest aligning supplemental insulin orders with BGL ranges. Any final design solution would need to take into account both these issues (where it could be a matter of determining which errors are considered more problematic).

6.3. Prescription of insulin

6.3.1. Subcutaneous routine insulin orders Although subcutaneous charts typically require users to review and prescribe routine insulin daily (source: heuristic analysis), in practice clinicians tend to prescribe routine insulin several days ahead of time (source: task analysis). For example, in one reported instance where insulin had been prescribed for a number of days at once, a medical officer, who wished to change the pre‐prescribed routine orders, was forced to cross out and initial the existing orders, and then re‐prescribe new orders. At the minimum, this practice can lead to visual clutter and illegibly small handwriting that could in turn lead to dosing errors. More importantly, according to endocrinologists we interviewed, pre‐prescribing multiple days of routine insulin could lead to dangerous hypoglycaemic events (source: task analysis interviews with clinicians). We argue that the way that routine insulin orders are presented in many charts may encourage users to inappropriately prescribe insulin for multiple days ahead of time. For example, subcutaneous charts and regular medication charts typically group several days’

68

worth of routine orders together in a table that is separate from the BGL record. Arguably this separation downplays the dynamic relationship between blood glucose levels and insulin, which may discourage users from remaining vigilant to the need to make revisions to the routine insulin order based on BGL readings. Potential design solution One potential design solution to address this issue is to align routine orders with their corresponding BGL record on a day by day basis (as illustrated in Figure 9). The idea is that this will emphasize the relationship between blood glucose levels and routine insulin doses. Within each day, the use of shaded meal‐based cells could also be used to create a perceptual separation between days (see Figure 9). We argue that this layout is likely to reduce the likelihood of users pre‐prescribing several days’ worth of routine insulin because (1) the shaded meal‐based cells provide a perceptual barrier between different days, and (2) the presence of a blank BGL record above a routine order would violate the natural progression of the user’s tasks (i.e., the requirement to assess the patient’s condition before insulin is ordered and administered).


Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0





Lunch Lunch Lunch





Figure 9: Example of the date columns of a BGL record directly aligning with the date columns of a routine insulin order record.

6.3.2. Intravenous fixed insulin orders Some intravenous insulin charts utilise a fixed schedule for insulin orders, which provides set infusion rates based on a patient’s BGL range (e.g., if the BGL reading is between 5 and 7 mmol/L, the patient receives 1 unit/hr of intravenous insulin). However, in our task analysis interview, clinicians expressed concern that, when a patient’s BGL reaches the highest prescribed range, the set infusion rate remains constant until the prescriber returns and writes a revised fixed schedule (source: task analysis interviews with clinicians). Potentially, fixed schedules decrease the likelihood of an adaptive insulin therapy based on a patient’s glucose levels, and increase the likelihood of a patient remaining on a constant and inappropriate rate of insulin. This means that the patient may be reliant on the treating nurses to contact prescribing medical officers (whilst leaving patients’ blood glucose levels to deteriorate) in order to ask them to return to the chart

69

and re‐document a new dosage regimen. Endocrinologists have questioned whether it is appropriate to leave nursing staff with this level of responsibility (source: task analysis interviews with clinicians). The fixed schedule intravenous chart favoured by all of our evaluators in the heuristic analysis (see Figure 20, Appendix C) was designed with this concern in mind (source: task analysis interviews with clinicians). The chart, presented on a two‐sided A4 page in portrait orientation, restricts the number of BGL record time‐columns to 24. This layout acts as a forcing function for regular insulin order revision, as users are required to turn the chart over (or start a new chart) every day (or two days, depending on BGL recording frequency), in the hope that this will prompt revision of the insulin order if needed. Although this strategy is advantageous from a practical standpoint, the use of an A4 page means that the chart was regarded by our evaluators as somewhat visually cluttered and cramped (e.g., columns were too narrow to accommodate size 14 handwriting, compressed and small fonts were used, alerts and special instructions were not salient, and bold lines rather than spaces were used to separate chart sections, making them distinct). Potential design solution One design solution for intravenous infusion charts that utilize a fixed schedule for insulin orders would be to include a restricted number of BGL record time columns (e.g., 24) but use an A3 sized page in landscape orientation. This solution means that there is scope to unclutter the display, whilst still providing a forcing function for users to revise the infusion rate (every two days at the minimum). Another issue that was raised by some of the subject‐matter experts we interviewed was that some existing charts involved prescribing a range of insulin doses rather than specific values. This was seen as problematic because it requires a non‐expert to determine what the actual dose ought to be (within the ranges specified – where these ranges could be substantial). We suggest that prescribing specific dose values may help reduce ambiguity in these cases.

6.3.3. Intravenous variable insulin orders In contrast to charts that involve fixed dose schedules, some charts involved variable intravenous insulin orders. These variable orders require users to adjust insulin doses by a percentage or proportion, according to patients’ blood glucose levels. Variable intravenous insulin orders typically utilise algorithms that take into account the patient’s current insulin rate. In its simplest form, some charts provided an algorithm that provided a series of blood glucose ranges with a corresponding action to continue, increase, or decrease the current insulin rate by a certain proportion (see Figure 21, Appendix C). Other charts were found to use more complex algorithms, such as a three‐dimensional adjustment table (see Figure 22, Appendix C). These systems require users to consider three variables; current insulin rate, current BGL, and BGL movement in the previous hour. The user is required to (1) hold in mind (or use their fingers as markers) the current insulin rate and current BGL, (2) mentally calculate the change in BGL, (3) input all three values into the algorithm adjustment table, and (4) mentally calculate the new insulin rate based on the information contained in the appropriate cell. We consider that this system likely to place a large cognitive load on users and we anticipate that this system would be prone to errors through misremembering, miscalculation or confusion, especially in

70

pressured or otherwise difficult situations (source: heuristic analysis). However, the use of three parameters may well yield a more appropriate insulin dose if the algorithm can be employed correctly. Potential design solution Any design solution to reduce errors in the use of variable insulin orders will obviously depend on whether the simplest adjustment method (based on current BGL only) is being used or whether the more complex three parameter algorithm is deployed. If a chart is using the simplest adjustment method then we suggest that one potential design solution could be to take advantage of the previously advocated BGL quasi‐graph display (as suggested in 6.1.1) and single parameter colour coded track and trigger system (as suggested in 6.1.2). One could align the coloured row ranges of the BGL record with corresponding ranges of the adjustment table (see Figure 10 below) so the user just has to scan across from the latest BGL reading to determine the appropriate insulin adjustment. The adjustment table ranges could be coloured to match the BGL record, to decrease the chances of row shift errors (i.e., accidentally reading the adjustment from the wrong row). This solution prevents users from having to visually compare a patient’s recorded BGL with a separate table of BGL ranges to determine the appropriate adjustment action. This integration of altering and action systems should help reduce the user’s cognitive load, potentially reducing decision times and the likelihood of adjustment errors. Blood Glucose Level Record Write BGL (mmol/L) in corresponding range box

Date DateAdjustment of Insulin Infusion Action

Time Time

> 20.0 > 20.0 Increase current rate by 1mL/hour (1 unit/hour) and inform RMO

16.1 - 20.0 16.1 - 20.0 Increase current rate by 1mL/hour (1 unit/hour) and inform RMO

12.1 - 16.0 12.1 - 16.0 Increase current rate by 1mL/hour (1 unit/hour)

8.1 - 12.0 8.1 - 12.0 Continue at current rate

4.0 - 8.0 4.0 - 8.0 Reduce current rate by 50%

< 4 < 4 Cease insulin infusion. Infuse 50mL bolus of 5% glucose.

Blood Glucose Level Record Adjustment of Insulin Infusion

Figure 10: Example of a BGL record’s colour coded range rows aligned with the corresponding colour coded blood glucose range rows of an adjustment of insulin infusion guideline. Alternatively, if charts adopt the more complex three‐dimensional algorithm then one option is to separate the algorithm table into three independent sub‐tables according to current insulin rate, with ‘current BGL’ columns rearranged as rows (incorporating the track and trigger colour code), and ‘BGL movement in last hour’ rows rearranged as columns (see Figure 11).

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Current Insulin Rate 0.1 - 1.9 units/hrBGL movement in last hour

BGL >5 BGL 3.1 - 5 BGL 0 - 3 BGL 0.1 - 1.9 BGL 2 - 2.9 BGL 3 - 5.9 BGL > 6

Current BGL

>15 2 units/hr 2 units/hr 1 units/hr 0.5-1 units/hr no change no change 0.1-0.5 units/hr10.0 - 14.9 1-1.5 units/hr 1 units/hr 0.5 -1 units/hr 1 units/hr no change 0.1-0.5 units/hr 0.1-1 units/hr8.1 - 9.9 1 units/hr 0.5-1 units/hr 0.5 units/hr 1 units/hr no change 0.1-0.5 units/hr 0.1-1 units/hr6.5 - 8.0 0.5 units/hr 0.5 units/hr no change no change 0.1-0.5 units/hr 0.1-1 units/hr 0.1-1 units/hr4.0 - 6.4 no change no change no change 0.1-1 units/hr 0.1-1 units/hr 0.1-1 units/hr 0.1-1 units/hr

Current Insulin Rate 2.0 - 4.9 units/hrBGL movement in last hour BGL >5 BGL 3.1 - 5 BGL 0 - 3 BGL 0.1 - 1.9 BGL 2 - 2.9 BGL 3 - 5.9 BGL > 6

Current BGL

>15 2-3 units/hr 2 units/hr 1-2 units/hr 1 units/hr no change no change 1-1.5 units/hr10.0 - 14.9 2 units/hr 1.5 units/hr 1 units/hr 1 units/hr no change 1 units/hr 1-1.5 units/hr8.1 - 9.9 2 units/hr 1-1.5 units/hr 0.5 units/hr no change 0.5 units/hr 1-2 units/hr 1.5-2 units/hr6.5 - 8.0 1 units/hr 1 units/hr 0.5 units/hr no change 1 units/hr 1-2 units/hr 1.5-3 units/hr4.0 - 6.4 no change no change no change 0.5-1 units/hr 1-2 units/hr 1-2 units/hr 1.5-3 units/hr

Current Insulin Rate 5 - 10 units/hrBGL movement in last hour BGL >5 BGL 3.1 - 5 BGL 0 - 3 BGL 0.1 - 1.9 BGL 2 - 2.9 BGL 3 - 5.9 BGL > 6

Current BGL

>15 3-4 units/hr 3 units/hr 2 units/hr 1-2 units/hr no change no change 1-2 units/hr10.0 - 14.9 3 units/hr 2-3 units/hr 1-2 units/hr 1 units/hr no change 1-2 units/hr 2 units/hr8.1 - 9.9 2-3 units/hr 2-3 units/hr 1 units/hr no change 1-2 units/hr 2 units/hr 2-3 units/hr6.5 - 8.0 1-2 units/hr 1 units/hr 1 units/hr 1 units/hr 2 units/hr 1-2 units/hr 2-3 units/hr4.0 - 6.4 no change no change no change 1-2 units/hr 2-3 units/hr 3-4 units/hr 3-5 units/hr

Figure 11: Example of an algorithm for insulin adjustments separated into three separate tables based on current insulin rate, utilising colour coded blood glucose range rows that correspond to the colour coded range rows of a BGL record’s track and trigger system. The principle behind this redesign is that the user should be able to systematically address each parameter without having to concurrently hold in mind the current insulin rate and current BGL. Using this algorithm, the user would first select the appropriate table based on the patient’s current insulin rate, and then match the current BGL in the BGL record with that in the appropriate algorithm table. In one example of a three parameter algorithm (see Figure 22, Appendix C), one problem noted by evaluators was that users were required to effectively mentally rotate the horizontally‐presented BGL record through ninety degrees to get it to correspond with the vertically‐presented BGL values in the algorithm table. We argue that this is likely to increase cognitive load. A solution to this would be to present both the BGL record and the BGL values in the table in the same orientation (see Figure 11 above, where BGL values are horizontally aligned, presuming a BGL record that is also horizontally aligned). Another suggestion for making a three parameter algorithm easier to use would be to utilize an A3 sized page in landscape orientation (as recommended in section 6.3.2) and ensure that the algorithm table can be placed side by side with the BGL record and insulin administration record (i.e., rather than above or below, or on a separate page). This allows direct visual comparisons to be made between the BGL ranges across the inside pages (see Figure 12).

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Current Insulin Rate 0.1 - 1.9 units/hr

BGL movement in last hour


Current BGL

>15 2 units/hr 2 units/hr 1 units/hr 0.5-1 units/hr no change no change 0.1-0.5 units/hr

10.0 - 14.9 1-1.5 units/hr 1 units/hr 0.5 -1 units/hr 1 units/hr no change 0.1-0.5 units/hr 0.1-1 units/hr

8.1 - 9.9 1 units/hr 0.5-1 units/hr 0.5 units/hr 1 units/hr no change 0.1-0.5 units/hr 0.1-1 units/hr

6.5 - 8.0 0.5 units/hr 0.5 units/hr no change no change 0.1-0.5 units/hr 0.1-1 units/hr 0.1-1 units/hr

4.0 - 6.4 no change no change no change 0.1-1 units/hr 0.1-1 units/hr 0.1-1 units/hr 0.1-1 units/hr

Current Insulin Rate 2.0 - 4.9 units/hrBGL movement in last hour


Current BGL

>15 2-3 units/hr 2 units/hr 1-2 units/hr 1 units/hr no change no change 1-1.5 units/hr

10.0 - 14.9 2 units/hr 1.5 units/hr 1 units/hr 1 units/hr no change 1 units/hr 1-1.5 units/hr

8.1 - 9.9 2 units/hr 1-1.5 units/hr 0.5 units/hr no change 0.5 units/hr 1-2 units/hr 1.5-2 units/hr

6.5 - 8.0 1 units/hr 1 units/hr 0.5 units/hr no change 1 units/hr 1-2 units/hr 1.5-3 units/hr

4.0 - 6.4 no change no change no change 0.5-1 units/hr 1-2 units/hr 1-2 units/hr 1.5-3 units/hr

Current Insulin Rate 5 - 10 units/hrBGL movement in last hour


Current BGL

>15 3-4 units/hr 3 units/hr 2 units/hr 1-2 units/hr no change no change 1-2 units/hr

10.0 - 14.9 3 units/hr 2-3 units/hr 1-2 units/hr 1 units/hr no change 1-2 units/hr 2 units/hr

8.1 - 9.9 2-3 units/hr 2-3 units/hr 1 units/hr no change 1-2 units/hr 2 units/hr 2-3 units/hr

6.5 - 8.0 1-2 units/hr 1 units/hr 1 units/hr 1 units/hr 2 units/hr 1-2 units/hr 2-3 units/hr

4.0 - 6.4 no change no change no change 1-2 units/hr 2-3 units/hr 3-4 units/hr 3-5 units/hr

Blood Glucose Level Record Glucose Level

Write BGL (mmol/L) in corresponding range box

Date Date

Time Time

>15 >15

10.0 - 14.9 10.0 - 14.9

8.1 - 9.9 8.1 - 9.9

6.5 - 8.0 6.5 - 8.0

4.0 - 6.4 4.0 - 6.4



Insulin AdministrationAlgorithm for Insulin

Adjustments

Figure 12: Example of algorithm for insulin adjustments presented adjacent to a BGL record and insulin administration record, on an A3 sized (landscape orientation) chart.

6.3.4. Subcutaneous standing supplemental insulin orders Clinicians currently disagree (source: task analysis interviews with clinicians) as to whether subcutaneous charts should require users to revise supplemental insulin orders daily or to revise orders only when clinically necessary (i.e., a standing order). Some clinicians argue that standing orders act a failsafe against junior medical officers who may neglect to prescribe insulin altogether, whilst others argue that standing orders may discourage nurses from reviewing patients’ insulin needs. Although these issues are beyond the scope of the current project, we acknowledge that chart users can often use standing orders incorrectly (source: task analysis). Even on those charts that provide instructions (e.g., supplemental insulin orders are “valid until ceased or changed”, see Figure 23, Appendix C), chart users often still re‐prescribe supplemental insulin each day, even to the point of directly transcribing the previous day’s doses. In one reported instance, an endocrinologist regularly shaded this instruction with a yellow highlighter as a signal to other chart users (source: task analysis), suggesting that the instructions were not salient enough to capture users’ attention. Potential design solution Presumably, the daily revision of routine insulin may prompt users to also review standing supplemental insulin orders. Thus it is important that any design solutions that discourage daily reviews of standing supplemental orders do not also discourage daily reviews of routine orders (the importance of which is discussed in section 6.3.1.).

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If a subcutaneous chart utilizes standing supplemental insulin orders then one potential solution could be to perceptually separate routine and supplemental orders to discourage users from pairing these tasks. For example, the range rows of the supplemental insulin orders could be aligned with the ranges rows of the BGL record (as suggested in section 6.2.2.), and the date columns of the routine insulin orders could be aligned with the date columns of the BGL record (as suggested in section 6.3.1.) (see Figure 13 below).



Time Time / / / / /




8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0




Lunch Lunch Lunch






Figure 13: Example of visually separated routine insulin orders and supplemental insulin orders.

6.3.5 Incorrect use of Stat/Phone order Most subcutaneous charts include a record for stat/phone insulin orders, which are used in two situations: (1) if a Medical Officer requests to be contacted with a patient’s BGL prior to prescribing an insulin dose; or (2) if a patient has been receiving insulin and no dose has been ordered. In both instances, the nurse is required to call the treating prescriber to obtain a telephone order for the dose and document that a telephone order has been taken (QH, 2009). Reports suggest (source: task analysis interviews with clinicians) that stat/phone orders for insulin can cause confusion among hospital staff. Often it is unclear to users that the stat/phone order record only provides recognition of the order, rather than documenting the actual administration of the insulin. Consequently, the administration of stat/phone ordered insulin is not recorded in the administration record (source: task analysis). The position of the stat/phone orders relative to the insulin administration record may contribute to this confusion. Chart designs that present stat/phone orders below administration records (see Figure 23, Appendix C) do not match the sequence of tasks users naturally engage in when making an order. These charts require users to (1) refer to the BGL record and insulin administration record, (2) move down the page to write in the stat/phone record, and then (3) (counter‐intuitively) move back up the page to write in the insulin administration record. We argue that this requirement to move back up the page may contribute to the neglected documentation of administrated insulin.

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Potential design solution We suggest that a best practice chart design would involve placing of the stat/phone order to match users’ natural sequence of tasks, relative to the BGL and insulin administration record. For example, stat/phone orders could be positioned between routine insulin orders and the insulin administration record (see Figure 14 below). This design allows users to progressively work down the chart, such that the order of displays matches the order of tasks. For example, the user (1) examines blood glucose levels and/or notices that no dose of routine insulin has been ordered, (2) calls the treating prescriber and documents the recognition of the stat/phone order, and (3) then documents the administration of the stat/phone insulin in the insulin administration record. Note that this suggestion violates (to some extent) the recommendation described in section 6.1.1, to keep BGL and administration records close together as, although the administration record is aligned with the BGL record (such that the user can document both values in the same time column), the spatial separation of the records may encourage delayed insulin administration after BGL readings are taken. Any complete design solution may involve a compromise that acknowledges both these issues.



Time Time / / / / /




8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0




Lunch Lunch Lunch



Stat/Phone Insulin Orders







Figure 14: Example of an insulin administration record presented after insulin orders records, including stat/phone insulin orders.

6.3.6. Overuse of Stat/Phone orders

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There is also a concern amongst subject‐matter experts (source: task analysis) that the inclusion of stat/phone orders may encourage a sliding scale approach to insulin prescription, whereby clinicians (especially those not expert in diabetic management) fail to prescribe routine insulin altogether, and instead make recurring ad‐hoc telephone orders for ‘one‐off’ doses of insulin. On the other hand, charts with no telephone order section at all do not allow nurses to document an unanticipated one‐off dose when it is clinically necessary (e.g., for patients with abnormally high blood glucose levels between meals) (source: task analysis interviews with clinicians). Potential design solution Although these issues should primarily be addressed via training, we suggest that chart design could offer a partial solution if routine and supplemental orders were positioned in such a way that chart users will naturally prioritize them over stat/phone orders. For example, routine and supplemental insulin orders could be placed above, or to the left of, stat/phone insulin orders (see Figures 14 and 15, respectively), as information presented in the left, or towards the top, of a display is normally attended to first (Preece et al., 2009).



Supplemental Insulin Orders Stat/Phone Insulin Orders




Date Date

Time Time






8.1 - 12.0 8.1 - 12.0

4.0 - 8.0 4.0 - 8.0






Figure 15: Example of a stat/phone insulin order presented to the right of routine and supplemental insulin order records. Note that the latter suggestion (see Figure 15 above) may contradict the recommendation in section 6.3.5. that the placement of the stat/phone order table should be determined by task order, as users would be required to unnaturally move from the stat/phone orders at the bottom of the page to the insulin administration record towards the top of the page. Again, a complete design solution may have to reflect a compromise.

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6.4. General presentation considerations

6.4.1. Chart title area and headings Insulin charts differ in the way in which their titles are presented. Charts typically display titles either at the top of the page(s) and/or vertically along page edges. Within the title itself, many charts do not specify the patient population (i.e., adult or paediatric) or clearly distinguish between the routes of insulin administration (i.e. ‘subcutaneous’ or ‘intravenous’), leaving the user to interpret the correct route (in one example, the undefined acronym ‘SC’ for subcutaneous was incorporated into an insulin order table on the reverse side of the chart). Some insulin‐specific charts even omit the distinction altogether, leaving the user to document the route of administration (source: task analysis systematic descriptions, see Table 20, Appendix B). Potential design solution We suggest that insulin charts present titles at the top of both the front and reverse pages (and also on the page edge if necessary for filing purposes). Chart titles should specify both the patient population and the insulin route. It may be beneficial to also present insulin routes in bold font to help users clearly differentiate between subcutaneous therapy charts and intravenous therapy charts (see Figure 16). We also recommend that the name of the facility or organisation should not be formatted in an overly prominent fashion. This information is of little relevance to the chart’s main role as a tool to achieve targeted glycaemic control, and any attention drawn to the name or logo of the facility or organisation is attention drawn away from more important information on the chart (Preece et al., 2009).

Insulin Subcutaneous Order and Blood Glucose Record - Adult

Facility: __________________________________________________________________________

Ward: ___________________________________________________________________________

Figure 16: Example of a chart title including insulin route (presented in bold font) and patient population We also recommend that insulin charts display important headings in a consistent and prominent fashion. For example, headings for insulin orders could be presented in white font on a black background, with corresponding symbols (see Figure 17). This (1) flags the three areas that prescribers may need to record in, and that nurses are required to check (i.e., the three areas for insulin orders are tied together), and (2) provides a readily identifiable cue that users can link to appropriate instructions.

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Phone/Stat Orders

Figure 17: Example of headings presented white font on a black background, and with corresponding symbols.

6.4.2. Use of abbreviations Insulin charts include a large number of abbreviations and acronyms (source: task analysis systematic descriptions, see Table 22, Appendix B). The consequences of misinterpreting abbreviations are many, and have even resulted in patient injury and death (Cohen, 2007). For example, there are reports that the acronym ‘SS’ (for sliding scale) has been misinterpreted at ‘55’ units of insulin, and the acronym ‘DC’ (for ‘discontinued’ insulin orders) has been misread as ‘discharge’ the patient from hospital (source: task analysis interviews with clinicians). Similarly, the abbreviation ‘U’ for units of insulin, if placed after a dose, can be misread as the number zero (0) resulting in a ten‐fold over‐dosage. In one documented instance, an insulin order written as ‘5U Humalog’ was misread as 50 units of Humalog, meaning that the patient erroneously received ten times more insulin than required (on two separate occasions). As a result, the patient suffered respiratory distress, cardiopulmonary arrest, and remained on mechanical ventilation until they died a week later (Cohen, 2007). In our own research (Horswill et al., 2010), we asked a large sample of health professionals (mainly nurses) to identify the intended definition of a list of acronyms used on patient observation charts, using a multiple‐choice format. A substantial proportion of the sample incorrectly interpreted many of the acronyms, which were presumed common knowledge by chart designers. That is, it is not safe to assume that all chart users will be familiar with even commonly used acronyms or abbreviations. We also found that terminology both within and across many insulin charts was inconsistent. For example, we found charts differed in their use of blood sugar level (BSL) versus blood glucose level (BGL), sometimes even within the same chart; (see Figure 24, Appendix C), and there were also alternating uses of insulin rate versus insulin infusion rate. Given that many clinicians work in multiple departments and hospitals, this type of lack of standardisation may slow performance and induce clinical errors (Preece et al., 2009).

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Potential design solution First, we recommend that full words be used over abbreviations where practically possible, as full words are more likely to be immediately understood by all chart users, whereas acronyms or abbreviations run the risk of being misunderstood or not recognized (especially by less experienced or relief staff) (Preece et al., 2009). Ideally, research should be undertaken to determine the level of understanding of particular terms by both novice and experienced chart users in order to allow the best understood term to be used. Second, we recommend that the term ‘units’ be pre‐printed in dose cells to prevent charts users from writing the full or abbreviated term themselves (this is a practice already used in the Queensland charts). Further, if the chart design requires adjacent rows to contain ‘units’, alternate rows should be shaded to discourage row shift errors (see Figure 18 below).

units units units units units units



Figure 18: Example of insulin dose cells with preprinted units, with visually differentiated rows.

6.4.3. Clinicians’ initials The use of clinicians’ initials on charts to authorise insulin orders and insulin administration has also led to misinterpretation. In a recent Australian incident, a nurse mistook a doctor’s initials ‘SB’ as ‘53’ units (source: task analysis interviews with clinicians). The nurse consequently administered 53 units of insulin, instead of the required 8 units, which caused the patient to overdose on insulin and suffer a severe hypoglycaemic event. Potential design solution One potential design solution would be to make sure that the cells for dose and initials were formatted differently to one another (e.g., different size, dimensions, borders, shading). In addition, the dose and initial cells could be physically separated or, if this is not possible, a high visibility divider (e.g., a bold line) could be placed between the dose and initial cells.

6.4.4. Prescribers’ details Many of the charts that we reviewed required prescribing doctors to provide their name and signature at various points in the form. This was typically a problem because the space provided to write in these details was frequently far too small for purpose (where making

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these spaces larger was not practical). In addition, even the space that was required for these details often meant that the space for other important information was often limited, leading to cramped design. In some charts, only the first prescriber provided their full name and signature while subsequent prescribers only provided initials, which might also be a problem in terms of identifying these individuals. Potential design solution One potential design solution to address these issues would be to add a prescriber details table, presented separately from the monitoring and insulin order areas, in which clinicians can record their names, signatures and initials (see Figure 19). This would act as a legend for identifying all prescribers, so that prescribers would only have to provide their initials elsewhere on the form, such as next to a prescribed insulin dose (which would require far less space) but it would be possible to look up their full details if necessary.

Prescriber Details Name Signature Initials

Prescriber 1:

Prescriber 2:

Prescriber 3:

Prescriber 4:

Prescriber 5: Figure 19: Example of an independent table for prescribers to record their name, signature and initials.

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7. Proposed Research Programme for Developing and Evaluating Insulin Charts In this section, we suggest an outline for a research programme for developing and evaluating insulin charts (while acknowledging that alternative strategies or variations on what is proposed may also be appropriate). 7.1. Phase 1: Develop new charts with associated preliminary instructional material

The first phase of the research would involve creating a number of alternative insulin charts (both subcutaneous and intravenous), the design of which would be guided by the outcomes of the informal task analysis and the heuristic analysis, as well as the recommendations of the evaluation team. Our starting point would be the pre‐existing charts identified in the heuristic charts as representing current best practice. Chart design usually involves finding an appropriate compromise between competing design considerations. However, it became clear in the current heuristic analysis that finding the right compromise for the design of paper‐based insulin charts will be particularly challenging (compared with finding the equivalent compromise for a general observation chart, for example). While the evaluators generated many suggestions for solving particular problems with the charts, the success of any complete solution will depend upon how those ideas can be made to work together on the page, and which considerations are given priority over others. In previous projects, we have developed one new prototype chart design (with variations based on clinical rather than human factors considerations) and compared it with existing charts. In contrast, for the proposed project, we envision generating a number of competing designs for the insulin charts (i.e., variations based on human factors considerations), which we would evaluate using behavioural experiments in order to identify the best performing subcutaneous and best performing intravenous chart (including comparisons with best‐practice charts in current use). Once a number of alternative chart designs have been developed, we would consult subject‐matter experts and chart users in order to refine the designs before commencing Phase 2 (i.e., empirical experimentation). The issue of user training has been kept separate from the process of chart design in our previous work. However, the general level of complexity associated with the insulin charts suggests that creating appropriate training materials may be crucial to the successful implementation of the new chart designs. In addition, the design of any training package is likely to interact with the design of the chart itself. For example, we will need to consider how much instructional information should be included in the chart, and how much should be relegated to separate training materials. This again involves striking a balance between a number of competing design considerations. If only minimal instructions are incorporated into the charts, then their functionality may be unclear. Conversely, excessive instructions might clutter the charts, reducing their usability. Similarly, although details relegated to separate instructional materials will not compete for attention with other information on the charts, these instructions will inevitably be less accessible.

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We envision that the final training materials for each new chart could potentially take the form of e‐learning package, which could be made available via the internet and/or DVD‐ROM. These e‐learning materials may also be supplemented by a summary poster designed to act as a simple primer or reminder, which could be displayed at nurses’ stations. Phase 1 of the proposed research project will involve designing and developing preliminary instructional material to accompany each of the different insulin chart designs to be tested in Phase 2. Note that, because these materials will be designed with the Phase 2 experiments in mind, they will be more rudimentary than the final training packages we propose developing in Phase 4. This preliminary instructional material will focus solely on how to use the charts. However, other aspects of training, such as persuasive communication as to why the chart ought to be used and completed properly, will be investigated in Phase 3.

7.2. Phase 2: Empirical experiments to assess user performance with the new charts, compared with one another and with existing charts

Once we have an array of insulin charts (i.e., multiple designs for both subcutaneous and intravenous charts) with accompanying training material, we will carry out a series of behavioural experiments to compare both novices’ and experienced health professionals’ performance when using the charts. Note that we will need to conduct a separate version of each experiment for subcutaneous and intravenous insulin charts. We will evaluate performance using objective outcome measures such as task accuracy and time to task completion. It is envisioned that we will run a series of experiments focussing on different aspects of chart function (in contrast to other charts we have designed, the insulin charts have multiple uses, and so we need to evaluate each of these). Experiments may range from highly controlled, highly focussed studies that concentrate on one particular aspect of the design (e.g. presenting precisely controlled stimuli using a computer‐based experimental system such as Superlab) to more realistic studies, using real charts as stimuli and a testing environment designed to be as close as possible to the reality confronted by users in a hospital ward. The aim will be to generate results to allow us to recommend, for both subcutaneous and intravenous insulin, the chart design that is likely to lead to the best user performance in the real world based on objective behavioural data. While the exact specifications of these experiments (including the total number of experiments) will depend on the outcomes of Phase 1, we provide examples of the types of study that would form part of this phase as follows. 7.2.1. Example 1: Experiment to measure performance in detecting abnormal BGL level. Participants (both novices and experienced health professionals) would first receive an introduction to each of the charts to be compared in the experiment, including relevant user instructions (each participant would view this material in a different random order). Next, participants would be presented with a large sample of charts with patient data pre‐recorded, and asked to indicate whether BGL is out of the normal range and, if so, what action needs to be taken. These charts would include an equal number of examples of each design being assessed, and would be presented in a random order. Participants’ responses would be timed and coded for accuracy (correct/not correct). This outcome data would be compiled by chart, and error rates (proportion of incorrect responses) and response times would be averaged across all the trials associated with

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each chart. From this, we would identify the charts (i.e., one subcutaneous chart and one intravenous chart) associated with the fewest errors and the shortest response times overall, and we would also examine whether there were any differences in performance between novices and experienced users (for example, one chart design might be optimal for novices while another might be optimal for more experienced users). 7.2.2. Example 2: Experiment to measure performance in determining the correct dose of insulin to administer. As in Example 1, participants would view the training associated with each of the charts in a random order, and would then be shown a series of different charts with patient data transcribed onto them. In this experiment, the task would be to identify the correct doses and types of insulin to be administered to each patient at a given time (e.g. lunchtime). Participant accuracy (dose and type of insulin correctly identified or not) and response times would be measured. Again, the charts associated with the fewest errors and the shortest response times would be identified and any novice/experienced user differences would also be examined.

Note that, on the basis of our previous research with observation charts, we anticipate that most errors associated with the completion of the insulin prescription information on the chart and the completion of BGL readings are likely to be due to factors other than chart design (e.g., the task of transcribing numbers into the correct place on the form is arguably more straightforward than other aspects of using the chart). To evaluate this, we anticipate conducting pilot work in which we might (for example) recruit a number of the relevant professional group and ask them to complete the insulin prescription on the charts and provide comment. Only if these data revealed an unexpectedly high proportion of errors would more formal work be carried out. Note that it is possible that the data from this phase will reveal that a pre‐existing chart outperforms all the new chart variations we have developed. If this occurs then we are likely to recommend that the pre‐existing chart should be the one to be taken into the next phase, or alternatively that the new chart should be re‐designed to address any apparent weaknesses. If results are not clear cut (for example, one chart design is better for novices and another is better for experienced users) then we will either redesign the new charts to take this discrepancy into account or further analyse our data (considering, for example, the extent to which experienced users would be disadvantaged if we were to choose a chart design that favoured novices) to guide our final recommendation.

7.3. Phase 3: User acceptance studies A key issue arising from our other chart work has been user acceptance of the finished products. Even the most optimally designed chart may be ineffective if health professionals are reluctant to use it or do not comply with the instructions for use. Hence, we propose running user acceptance studies in order to identify the key acceptance obstacles with the chart designs recommended for use as a result of Phase 2. The key outcome of these studies will be a series of recommendations that will increase the likelihood that the redesigned charts will be accepted by users (and will be incorporated into the final chart training packages developed in Phase 4).

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The theory of planned behaviour (Ajzen & Madden, 1986) will be used to identify those factors that facilitate or inhibit the acceptance of the chart designs. This is a model that has been used to predict a wide range of different behaviours (see Ajzen, 1991, for a review) and focusses on behavioural intention as the most proximal predictor of behaviour. Behavioural intention is a subjective estimate of the probability that one will perform a certain behaviour. While the ultimate goal is to promote behaviour change, in this phase we will focus on understanding and changing behavioural intentions associated with the use of the charts identified as best practice in Phase 2. According to the theory of planned behaviour, intentions are a function of three factors: attitudes, subjective norms, and perceived behavioural control.

• Attitudes are how favourable or unfavourable a person feels about performing the behaviour.

• The subjective norm is the perceived social pressure to perform or not perform the behaviour.

• Perceived behavioural control is whether you feel you have control over the behaviour or not. Each of these factors is based on underlying beliefs.

• For attitudes, the beliefs are the perceived outcomes of performing the behaviour weighted by the positivity of the outcomes.

• For subjective norms, the beliefs are those people and/or groups who would approve or disapprove of performing the behaviour weighted by one’s motivation to comply with those people and/or groups.

• For perceived behavioural control, the beliefs include those things that are seen as facilitating or inhibiting the performance of the behaviour weighted by the power that each of these factors has over behaviour.

We will use an augmented version of the model incorporating perceptions of self‐efficacy (Armitage & Conner, 1999) and a revised normative component (see Terry, Hogg, & White, 1999). Self‐efficacy, the perception that one is able to perform the behaviour, improves the prediction of behaviour that has an internal locus of control (when factors affecting the behaviour are due to the individual rather than due to external factors). A revised normative component, taking into account the groups that are contextually relevant for the performance of the behaviour and whether the behaviour is normative for the group, more accurately predicts the influence of social factors. One of the strengths of the model is that it allows researchers to identify which of the underlying beliefs differentiates between those who intend to perform a behaviour (i.e. comply fully with using a chart appropriately) and those who do not intend to perform a behaviour (i.e. fail to comply. These differences then become an important focus for persuasive communication to change the beliefs of those with lower intentions with the goal of increasing intentions to perform the behaviour. There will be two studies in this phase. Each study will be conducted for both the subcutaneous and intravenous insulin charts identified as best practice in Phase 2. In the first study, a small sample of around 20 health professionals will be asked to identify (1) the key beliefs related to attitudes, norms, and behavioural control, (2) the potential outcomes of using or failing to use the chart, (3) the internal and external factors that would facilitate or inhibit the use of the chart, and (4) the groups of people who would approve or disapprove of using the chart. In the second study, a much larger sample of potential users of the chart will be asked to complete a questionnaire regarding the best‐

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practice chart identified in Phase 2 (items will be developed from the outcomes of the first study) assessing their (1) willingness to use the chart, (2) attitudes towards the chart, (3) beliefs about whether others would use the chart, (4) whether others would want them to use the chart, and (5) a measure of the extent that participants felt it was within their control to use the chart. The underlying beliefs will also be assessed. Analyses will indicate which factors are important predictors of willingness to use the redesigned charts, and also which beliefs differentiate between people with different levels of willingness to use the chart. Identifying the issues that are likely to affect the adoption of the best‐practice charts will allow us to develop strategies to tackle any anticipated non‐compliance in advance. For example, intentions and beliefs identified as problematic for chart uptake will be targeted for modification by persuasive communications that will be incorporated into the final training packages to be developed in Phase 4.

7.4. Phase 4: Development and validation of the full training packages Once the obstacles to chart implementation and acceptance have been identified in Phase 3, we will develop appropriate training involving persuasive communication techniques in order to target these obstacles. In addition, the preliminary instructional material developed in Phase 1 for the training of experimental participants will be modified and developed for general use. The instructional material and the persuasive communication material will be combined into professional‐quality training packages (i.e. ready for implementation) for the two best practice charts identified in Phase 2. While the exact medium of the training packages to accompany the charts will not be finalized until this stage is reached, we anticipate that they are likely to take the form of online e‐learning packages and/or DVD‐ROM, potentially supplemented by paper‐based materials (e.g. a poster for display at nurse stations and/or a user manual). Once the training packages have been finalized, we will conduct a final series of behavioural experiments to validate the training and chart packages in their final forms. These experiments will follow similar protocols to the studies in Phase 2 (where accuracy and response time to various tasks will be evaluated), but will only involve the two recommended charts with their accompanying training packages (plus control conditions, as appropriate). In this work, we will also investigate the extent to which the persuasive communication training influences the opinions of users and has the desired effect of minimizing perceived obstacles to the deployment of the charts and compliance with their instructions. These experiments are crucial to ensure that (1) the training has the desired effect and (2) the final training and chart packages work together (e.g., we have not introduced any elements into the final versions of the training packages that compromises chart effectiveness).

7.5. Final outcomes of research programme The final outcomes to the proposed research will be a best practice intravenous insulin order chart and a best practice subcutaneous insulin order chart (both with blood glucose level monitoring), selected using objective performance data, which would both be suitable for national implementation. These two charts will be supported by validated training materials (produced to a professional standard) that would be ready for practical nationwide implementation with minimal investment (for example, we envision that the training packages could involve an online e‐learning package, available across Australia, where implementation costs would involve hosting, maintaining, and updating the material as necessary over time, possibly supplemented by paper‐based materials, such as

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posters and manuals). In addition, guidelines for allowable modifications to the charts to account for appropriate regional variations in facilities and clinical practice will be provided.

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Appendix A: Insulin charts submitted by the Australian Commission on Safety and Quality in Health Care. Type Hospital of area

health service Title of chart supplied

Intravenous Queensland Intravenous Insulin Form (current version) Queensland Intravenous Insulin Form (proposed version) Sydney West Area Intravenous Insulin Infusion Blood Glucose Chart Royal Perth Insulin Infusion Chart Swan Kalamunda Intravenous Insulin Administration Chart Fremantle Fremantle Insulin Infusion Chart Lyell McEwin Intravenous Actrapid Infusion Standard Protocol &

DKA/Type 1 Protocol (same expect for special instructions)

Whyalla Insulin Infusion Chart Barwon Patient Insulin Infusion Management Chart Timboon Diabetic Treatment Sheet District/Southwest Diabetic Treatment Sheet Wimmera Diabetic Management Chart Subcutaneous Queensland Subcutaneous Insulin Form (current version) Queensland Subcutaneous Insulin Form (proposed version) Queensland Paediatric Subcutaneous Insulin Form (current version) Sydney West Area Adult Subcutaneous Insulin Prescribing Chart Statwell Subcutaneous Insulin Order and Blood Glucose Record Princess Margaret Subcutaneous Insulin Order and Blood Glucose

Monitoring Chart (for children) Swan Kalamunda Diabetic Inpatient Record and Insulin Medication Chart Lyell McEwin Insulin Subcutaneous Order and Blood Glucose Record Whyalla Subcutaneous Sliding Scale Chart Queen Elizabeth Insulin Sliding Scale Adelaide Prescription Sheets for Subcutaneous Pump Therapy Unknown Pink Diabetes Management Chart Tasmania Blood Sugar Record and Insulin Order Flinders Basal‐Bolus Insulin Drug Chart Not specified Cabrini Medication Record & Cabrini Insulin Order/Record Wangaratta Diabetic Management Chart Charles Gardiner Diabetes Sheet Medication Austin Regular Medications Chart Wimmera Regular Medications Charts Wangaratta Regular Medications Charts Eastern Health Regular Medications Charts Seymour Regular Medications Charts Victoria Women's WCH Regular Medications Charts Wodonga Regular Medications Charts Mount Gambier Frequent/Variable Medication Chart & Sliding Scale

Insulin Protocol

Appendix B: Features analysed in the preliminary descriptions of the Informal Task Analysis. Table 11: Percentage of charts that utilise various presentations of blood glucose levels Presentation of blood glucose levels

Percentage of charts

Standard table Graph Singular column Singular row Table with range rows

54% 22% 11% 8% 5%

Written number observations Drawn dot observations

78% 22%

Table 12: Percentage of charts that utilise various altering systems Altering systems


No track and trigger system Graphed single parameter track and trigger system Tabular single parameter track and trigger system

79% 16% 5%

BGL cut‐offs provided in instructions No BGL cut‐offs provided in instructions

51% 49%

Table 13: Percentage of intravenous charts that provide normal BGL ranges Intravenous BGL ranges


No normal range provided 4.1 mmol/L ‐ 12.1 mmol/L 5.0 mmol/L – 15.0 mmol/L; 4.0 mmol/L ‐ 8.0 mmol/L; above 4.0 mmol/L; 4.0 mmol/L ‐ 9.0 mmol/L; 6.0 mmol/L ‐ 9.9 mmol/L

42% 17% 8%

Table 14: Percentage of subcutaneous charts that provide normal BGL ranges Subcutaneous BGL ranges


4.0 mmol/L – 20.0 mmol/L No normal range provided 4.1 mmol/L – 19.9 mmol/L; 4.0 mmol/L – 15.0 mmol/L 4.1 mmol/L – 12.0 mmol/L

36% 29% 14% 7%

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Table 15: Percentage of charts that utilise various presentations of blood glucose frequency indicators Blood glucose frequency indicators


Instructions to check BGL at certain times each day Hour‐based tick boxes (e.g., hourly, 2 hourly) Meal‐based columns or rows (e.g., breakfast, lunch) No frequency indicators

43% 24% 19% 14%

Table 16: Percentage of charts that utilise various presentations of insulin administration records, relative to blood glucose levels Presentation of insulin administration records, relative to blood glucose levels


BGL aligned with Insulin administration BGL not aligned with Insulin administration (adjacent tables, same page) BGL not aligned with Insulin administration (separate pages or separate charts)

54% 41%

5%

Table 17: Percentage of charts that utilise various lengths (in hours) of BGL monitoring record Length of BGL monitoring record Percentage of

charts 48 hours 18 hours 40 hours 30 hours 24 hours; 14 hours 12; 25; 27; 28; 31; 35; 36; 56; 112; 126; and 168 hours

22% 16% 14% 8% 5% 3%

Table 18: Percentage of subcutaneous charts that specify when to record BGL, relative to mealtime Specify when to record BGL, relative to mealtimes


Tick box for ‘Standard’ which is defined as pre‐meals No specification Integrated into BGL table (before and/or after meals); written instructions

36% 29% 14%

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Table 19: Percentage of subcutaneous charts that utilise various presentations of routine insulin orders, relative to insulin administration records Presentation of routine insulin order relative to insulin administration record


No routine insulin orders on chart (or reference to another chart) Routine insulin order on the same chart and same page Routine insulin order on the same chart but reverse page No routine insulin orders on chart (but refers users to another chart)

49% 32% 16% 3%

Table 20: Percentage of charts that provide distinction between subcutaneous and intravenous insulin therapy Distinction between subcutaneous and intravenous insulin therapy Percentage of

charts Unclear distinction (i.e. the terms ‘subcutaneous’ or ‘intravenous’ are included somewhere on the chart, but not at the top) No distinction (i.e. same chart used for both therapies) Clear distinction (i.e. labelled ‘subcutaneous’ or ‘intravenous’ at top of chart)

38%

32% 30%

Table 21: Percentage of charts that preprint insulin ‘units’ or chart user ‘initials’ Preprint insulin ‘units’ or chart user ‘initials’


No use of pre‐printed insulin ‘units’ or chart user ‘initials’ Use of pre‐printed insulin ‘units’ Use of pre‐printed chart user ‘initials’

76% 24% 11%

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Table 22: Percentage of charts that utilise various abbreviations and forms of clinician authorisation Abbreviations and forms of clinical authorization Percentage of

charts BGL (Blood Sugar Level) IV (Intravenous) RMO (Resident Medical Officer) MO (Medical Officer) BSL (Blood Glucose Level) ADR (Adverse Drug Reaction) Hypo (Hypoglycaemia); PRN (take as needed); INR (coagulant response time); GP (General Practitioner); Nr (Nurse); RN (Registered Nurse) W (Weight); SC (Subcutaneous) QID (four times per day) HONK (Hyperosmolar Nonketotic Coma) Conc (Concentration), Vol (Volume) SS, TPN, DKA, HHS, REG, OHG, K+, Pharm, mis, N/S, DM, KCl, PREP, N/Saline, RN, ADR, AC, PC, REG, M, F, GLUC, KET, B, P, H, Wt, TDDI, MET, TDS, BD, GLU, KET, NSE, P’cy r/v, Imprest, SA02

62% 30% 27% 24% 22% 19% 16%

14% 11% 8% 5% 3%

Use of clinicians’ signatures only Use of clinicians’ initials only Use of both clinicians’ initials and signatures No use of either clinicians’ initials or signatures

46% 43% 8% 3%

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Table 23: Percentage of charts that utilise various colours for different purposes Colours and purposes of colour


Black Red Grey Green Purple Blue Pink, Yellow Orange

84% 54% 38% 16% 11% 8% 5% 3%

No colours used (black only) 14% Colour used as shading tool Colour refers to important/alerting information Colour used as a chart border

62% 54% 5%

Table 24: Percentage of charts that utilise various presentations of patient identification Presentation of patient identification Percentage of

charts

Written patient identification only Both written and labelled patient identification No patient identification

30% 62% 8%

Positioned in top right corner of page For folded A3 charts: inside page positioned in top left corner, and back/reverse page positioned in top right corner Positioned in top left corner of page Positioned in top centre of page

65% 16% 8% 3%

Table 25: Percentage of charts that utilise various paper size, orientation, and sidedness


A4 sized paper A3 sized paper

46% 54%

Portrait orientation Landscape orientation

41% 59%

One‐sided charts Double‐sided charts

19% 81%

Appendix C: Representative charts selected for Heuristic Analysis. Figure 20: Front and reverse pages of Queensland Insulin Intravenous Infusion Order and Blood Glucose Record – Adult (A4)

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Figure 21: Front and reverse pages of Fremantle Hospital and Health Service Insulin Infusion Chart (A4)

Figure 22: Outside and inside pages of Sydney West Blood Glucose Level (BGL) monitoring chart for IV Insulin Infusions (A3)

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Figure 23: Outside and inside pages of Queensland Insulin Subcutaneous Order and Blood Glucose Record – Adult (A3)

Figure 24: Front and reverse pages of Tasmania Blood Sugar Record and Insulin Order (A4)

Figure 25: Outside and inside pages of Sydney West Adult Subcutaneous Insulin Prescribing Chart (A3)

Figure 26: Mt Gambier Frequent/Variable Medication Chart (A4, one sided)

Figure 27: Outside and inside pages of Northeast Health Wangaratta Regular Medications chart (A3)

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Appendix D: Briefing report for evaluation team Background Information

Diabetes Mellitus Diabetes mellitus is a group of metabolic diseases caused by an absolute or a relative lack of the pancreatic hormone, insulin (Guthrie & Guthrie, 2008; Watkins, 2002; Gottschlich, 2001). The vast majority of diabetic cases fall into two broad categories: Type 1, caused by an absolute deficiency of insulin secretion; and Type 2, the result of a combination of resistance to insulin action and an inadequate compensatory insulin secretory response (Gottschlich, 2001). The prevalence of diabetes mellitus in Australia has increased from 2.4% in 1995, to 3.0% in 2001, and 3.5% in 2005 (Australian Bureau of Statistics, 2009a). This rise is cause for concern given that diabetes can contribute to illness, disability, poor quality of life, and premature death. Indeed, diabetes contributed to 10.1% of Australian deaths in 2009, as either an underlying or associated cause (Australian Bureau of Statistics, 2009b). Two different conditions can lead to a diabetic emergency: hyperglycaemia, a state in which an individual’s blood glucose level (BGL) is above normal physiological ranges; and hypoglycaemia, a state in which an individual’s blood glucose level is below normal physiological ranges. Ketoacidosis results from prolonged and exceptionally high hyperglycaemia, whilst unresponsiveness and eventual insulin shock result from hypoglycaemia (Pollak et al., 2006). Blood Glucose Control Diabetic patients need targeted glycaemic control when they are in hospital, arguably more than when at home, considering the stresses of critical illness and surgery when hospitalised (Moghissi, 2004). A rapidly growing body of literature suggests that, regardless of whether a patient has a known history of diabetes, in‐hospital hyperglycaemia is associated with increased mortality and morbidity. As such, meticulous glycaemic control can significantly improve clinical outcomes (Cheung & Chipps, 2010; Guthrie & Guthrie, 2008; Pomposelli et al., 1998; Zerr et al., 1997). Insulin Therapy Insulin is the most effective agent for achieving glycaemic control in hospitalised patients (Moghissi, 2004). It can be titrated easily, does not have a ceiling dose, and can be administered intravenously (though the vein) and subcutaneously (under the skin) (Lien et al., 2011). Inpatient insulin regimens must be matched or tailored to the specific clinical circumstance of the individual patient (Clement et al., 2004). Indications for intravenous (IV) insulin therapy include prolonged fasting, critical illness, pre surgical procedures, post organ transplantations, and during labour (Moghissi, 2004; Clement et al., 2004). In these patients, the intravenous route for insulin administration surpasses the subcutaneous route because of its rapid onset, effect in controlling hyperglycaemia, and overall ability to achieve glycaemic control. Subcutaneous (SC) insulin therapy is used to attain glucose control in those diabetic patients who don’t fall under the aforementioned

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intravenous categories (Clement et al., 2004), and is therefore the more common route of insulin administration. Intravenous Insulin Therapy A number of protocols have been developed to assist with titration of intravenous insulin infusion rates, and most hospitals have a preferred order set. Clinically favoured methods take into account patients’ insulin‐sensitivity levels (Lien et al., 2011). One way to achieve this is to adjust the insulin infusion according to the rate of change of glucose levels from hour to hour, using a multiplication factor to assist with titration. Other IV insulin protocols account for differences in patients’ insulin sensitivities by using a choice format (with the appropriate algorithm chosen according to level of sensitivity) (Lien, Feinglos & Corsino, 2010). Despite the effectiveness of intravenous insulin protocols for most patients, it is worth noting that there are patients for whom no protocol is perfect. An example is the highly insulin‐resistant patient, who may require large volumes of intravenous insulin. Similarly, the highly insulin‐sensitive patient, particularly those with renal failure and Type 1 diabetes, may require very small volumes of insulin. This type of patient will require the attention of an experienced prescriber, rather than a protocol alone (Lien, Feinglos & Corsino, 2010). Subcutaneous Insulin Therapy Evidence suggests that subcutaneous insulin administration should include three components to be effective: basal insulin (to inhibit hepatic glucose production overnight and between meals), bolus insulin (to facilitate mealtime glucose metabolism), and correction‐dose insulin (to provide real‐time adjustment of insulin dosing based on a patient’s insulin sensitivity) (Nau et al., 2010; Hirsch, 2009). Correction‐dose insulin is usually administered as an addition (or supplement) to the routine dose of bolus insulin as a specific algorithm based on total daily dose of insulin or patient weight (Hirsch, 2009). For instance, imagine that you are treating a diabetic patient with routine insulin (e.g. 10 units at each meal), and their blood glucose level increases by a clinically significant amount. With the ‘correction‐dosing’ approach, you can add extra insulin (e.g. 2 units) to their routine insulin (i.e. 10 + 2 = 12 units) to bring their glucose levels back down to an acceptable level. Similarly, if your patient’s glucose levels are too low, you can subtract an appropriate number of insulin units. Correction‐dose insulin is often confused with “sliding scale insulin”; however the difference between the two is crucial (Hirsch, 2009). Sliding scale insulin refers to subcutaneous insulin doses administered to reduce hyperglycaemia detected on routine blood glucose monitoring. Once again, imagine that you are treating a diabetic patient with elevated blood glucose levels. Using the sliding scale approach, if the patient’s blood sugar is between 10 and 14.9 mmol/L, 6 units of insulin should be administered; if it is between 15 and 19.9 mmol/L, 8 units should be administered; and if it is over 20 mmol/L, 10 units should be administered. In contrast to the correction‐dose approach, this sliding scale insulin is the only insulin the patient receives. Sliding‐scale insulin regimens incorrectly assume that all patients have similar insulin sensitivities, fail to adequately control hyperglycaemia, result in high rates of hypoglycaemia, and are associated with longer hospital stays (Queale, Seldler &

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Brancati, 1997). Perhaps more importantly, sliding scales have no track record of effectiveness; a Medline search of 52 trials from 1966 to 2003 demonstrated no clinical benefit from sliding scale insulin (Hirsch, 2009). Insulin Charts Intravenous and subcutaneous insulin charts ‐ used by both medical officers and nurses ‐ are the primary method used to monitor a patient’s blood glucose levels, and to document the associated insulin therapy. Despite their ability to help clinicians maintain targeted glycaemic control, the primary objective of diabetic management, insulin charts vary widely in their design across Australia. Empirical evidence has demonstrated that chart design can significantly affect a user’s decision time and accuracy when detecting abnormal physiological observations (Horswill et al., 2010), suggesting that differences in insulin chart designs may too affect the quality of care provided to diabetic patients. To date, only one known investigation has evaluated the impact of insulin chart design on the management of hospitalised patients with diabetes (Lehnbom et al., 2009). In a retrospective study comparing the management of three groups of diabetic patients, Lehnbom and colleagues compared the use of insulin and the management of hypoglycaemic events before and after the introduction of a new insulin chart. The new chart allowed the documentation of insulin prescription, sliding scale insulin, blood glucose levels and hypoglycaemic events. Although significantly more hypoglycaemic events were treated post‐implementation of the new insulin chart, the number of hypoglycaemic events without any documented treatment remained unchanged, as did the number of insulin dose omissions, and cross‐referencing between the new chart and standard medication chart was performed incorrectly for over half of patients. Insulin Chart Protocol The following draft protocol outlines the key steps a nurse (or prescribing medical officer) takes during the management of a diabetic patient. Where appropriate, the protocol branches into steps only applicable to intravenous or to subcutaneous insulin therapies. Although derived from Queensland Health guidelines (QH, 2008) (it may be helpful to refer to Charts 1 and 4 as you review the protocol), the overarching steps can be generalized to the remaining charts. This protocol is selected for demonstrative purposes because it is the most comprehensive; note that this does not mean that the Queensland charts or protocols are preferred. Identification and Demographics 17. Establish the need for either intravenous insulin or subcutaneous insulin and

select the appropriate chart. 18. Apply a patient identification label or (if unavailable) document the patient’s

name, reference number, date of birth, gender and address in the patient identification section of the chart.

19. The first prescriber must print the patient’s name under the patient identification label (to reduce the risk of the wrong patient’s identification label being placed on the form).

20. Document the Facility/Service, Year, and Ward/Unit.

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21. Cross reference with the Inpatient Medication Chart, by indicating that the Insulin Chart is in use.

22. Also cross reference with the Regular Medication Order (on the Inpatient Medication Chart) to ensure that staff refer to the insulin chart (e.g. “See insulin/BGL form”) and that insulin is not omitted from discharge medications.

Initial Blood Glucose Levels Frequency 23. Prescriber to indicate the initial frequency in which BGL will be monitored.

The BGL frequency should be reviewed and updated regularly (and re‐recorded appropriately). Intravenous: hourly BGL monitoring is typically required. Subcutaneous: BGL monitoring before meals and bed is typically required.

24. Document the diet the patient is to receive for the day. Alerts and Special Instructions 25. If not indicated on the chart, document the target BGL range for the patient.

Intravenous: BGL target range for most patients is 5‐10 mmol/L. Subcutaneous: BGL target range for most patients is 4‐8 mmol/L.

26. If patient requires tighter control of their BGL (e.g. due to pregnancy), use the communication areas (i.e. Alerts and/or Special Instructions boxes) to assist in defining specific BGL targets and notifications.

27. Prescriber to document whom to notify of any BGL that is out of the defined range. Intravenous: typically if less than 5 mmol/L; greater than 15 mmol/L; or three consecutive BGL readings greater than 10 mmol/L. Subcutaneous: typically if less than 4 mmol/L; greater than 20 mmol/L; or two consecutive readings greater than 20 mmol/L.

28. Document any special instructions related to the patient’s diabetes management in the space provided.

29. Document if the patient has received insulin treatment prior to admission, including the insulin type/s and the pre‐admission doses.

Initial Blood Glucose Monitoring 30. Document the date and time in the first column/row of the BGL record, and

the type of diet the patient is receiving (e.g. clear fluids, full diet). 31. Measure the patient’s BGL as per facility procedure then record the BGL

observation (depending on the chart this may involve plotting the BGL observation as a dot in the centre of the time column according to the y‐axis BGL values on the graph, or writing the numerical BGL observation in the row/table BGL record).

Initial Insulin Orders and Insulin Administration

Intravenous Intravenous insulin orders are divided into three components: Initial Infusion Rate, Revised Infusion Rate, and Second Revised Infusion Rate.

Subcutaneous Subcutaneous insulin orders are divided into three components: Routine, Supplemental/Variable, and Stat/Phone. Routine Insulin Orders

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Initial Infusion Rate • After performing and

documenting the BGL, commence the insulin infusion time and rate documented in the Insulin Infusion Order.

• Recommended (pre‐printed) initial infusion insulin rate and BGL ranges are typically provided as a safe starting point for junior prescribers and those minimally experienced in initiating intravenous infusions (alternate BGL ranges and infusion rates may be used).

• To prescribe an intravenous insulin infusion, document (below the BGL reading in the appropriate time column) the rate at which the insulin infusion rate is running in the row marked Insulin Infusion Rate.

• If the patient is receiving a meal or snack bolus of insulin, document the number of units given the row marked Meal/Snack Bolus and sign initial.

• Meal times (breakfast, lunch, dinner and pre‐bed) determine routine subcutaneous insulin rates. Meal times are pre‐printed to ensure insulin is given immediately before a patient eats (i.e. their meal should be in front of them). Each dose is prescribed in a different space according to the meal or time it is to be administered.

• In the prescribing space for the appropriate meal/time, prescriber to document the date, full trade name of the insulin, the units of insulin to be administered, and sign and initial each order (when writing up daily doses, it is appropriate to write up doses for the rest of the day and for the first dose/s of the following day).

Continued Blood Glucose Monitoring 16. Measure and document BGL at the next time point (indicated by the

determined BGL frequency initially documented). Intravenous

• If the BGL is less than 5mmol/L; suspend the insulin infusion, continue glucose infusion and notify prescriber.

• If the BGL is less than 4 mmol/L; suspend the insulin infusion, continue glucose infusion, initiate hypoglycaemia management (refer to Hypoglycaemia Management on back page of subcutaneous chart), notify prescriber, and document that hypo intervention has been initiated. Perform follow up BGLs according to

Subcutaneous • If the BGL is less than 4 mmol/L; initiate hypoglycaemia management (refer to Hypoglycaemia Management on back page of chart), notify prescriber and document that hypo intervention has been initiated. Perform follow up BGLs according to Hypoglycaemia Management and

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Hypoglycaemia Management and document treatment and response in medical record. One hypoglycaemia is resolved, recommence insulin infusion and review insulin orders.

• If the BGL is greater than 15 mmol/L; check that the insulin infusion is running, and notify prescriber. Prescriber to adjust insulin infusion rate. Perform a ketone test, document the result, and notify the prescriber accordingly.

document treatment and response in medical record.

• If BGL is greater than 20 mmol/L or if it is the second consecutive BGL greater than 15 mmol/L; notify the prescriber, perform a ketone test, document the result, and document the actions taken in the medical record.

Revision of Insulin Orders and Administration

Intravenous Subcutaneous

Revised Infusion Rate • Prescriber must review

the insulin infusion where there has been any BGL alert and/or daily before midday.

• To revise the insulin infusion rate, the authorized prescriber must cease the previous insulin infusion order, write “cease” and the reason (e.g. “adjust dose”) and sign their initials.

• Write the date/start time the infusion is to commence in the Revised Infusion Rate column of the Insulin Infusion Order.

• Prescriber to write in the revised infusion rates according to the pre‐printed BGL ranges or alternate BGL ranges, sign the order and print their name below the prescription.

Second Revised Infusion Rate

Supplemental/Variable Insulin • Patients may require a supplemental

dose of insulin if their condition, dietary intake or a concurrent medication is altering their insulin requirements (or if the patient has recently commenced subcutaneous insulin and optimal doses have not yet been determined). This may be in addition to a routine mealtime insulin dose or in addition to a routine basal insulin dose.

• Document the meal/time the insulin is to be administered, the type and dose of insulin to be administered in response to the standardized BGL ranges that are provided on the chart. Prescriber then to record name and sign the prescription (as required, prescriber to review and rewrite supplemental doses, then initial in the corresponding date columns).

• Prescriber then to document the administration of the supplemental insulin dose in the Administration Record section.

Stat/Phone Insulin Orders • Stat/Phone Insulin Orders are

made ff the prescriber wants to be contacted with a BGL reading prior to prescribing an insulin dose, or If the patient has been receiving

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• Repeat the above steps. • The insulin intravenous

infusion order can be revised up to 3 times in a 24 hour period.

insulin and no dose is ordered, the nurse must call the treating prescriber or the Medical Officer On‐Call for a phone order (the previous day’s order is not a recurrent dose order).

• In both situations, the nurse writes “ph” in the appropriate insulin dose box of the Routine Insulin Orders section to indicate that a phone order has been taken.

Potential User Errors Potential user errors are drawn from a single evaluator’s preliminary review of 37 Australian insulin charts and the research team’s structured interviews with three subject area experts. Misreading abbreviations Insulin charts include a large number of abbreviations and acronyms, especially for insulin prescriptions. The consequences of misinterpreting abbreviations and dose expressions are many, and have even resulted in patient injury and death (Cohen, 2007). For example, the abbreviation ‘U’ for units of insulin can be misread as the number zero (0) resulting in a ten‐fold over dosage. In one documented instance, an insulin order written as ‘5U Humalog’ was misread as 50 units of Humalog, meaning that the patient erroneously received ten times more insulin than required (on two separate occasions). As a result, the patient suffered respiratory distress, cardiopulmonary arrest, and remained on mechanical ventilation until they died a week later (Cohen, 2007). Similarly, anecdotal evidence (source: task analysis interviews with clinicians) suggests that the acronym ‘SS’ (for sliding scale) has been misinterpreted at ‘55’ units of insulin, and the acronym ‘DC’ (for ‘discontinued’ insulin orders) has been misread as ‘discharge’ the patient from hospital. The use of clinicians’ initials on charts to authorise insulin orders and insulin administration has also led to misinterpretation. In a recent Australian incident, a nurse mistook a doctor’s initials ‘SB’ as ‘53’ units (source: task analysis interviews with clinicians). The nurse consequently administered 53 units of insulin, instead of the required 8 units, which caused the patient to overdose on insulin and suffer a severe hypoglycaemic event. Terminology within and across insulin charts is also inconsistent. For example, charts differ in their use of blood sugar level (BSL) vs. blood glucose level (BGL); units vs. units/hr; and insulin rate vs. insulin infusion rate. Given that many clinicians work in multiple departments and hospitals, this type of lack of standardisation may slow performance and induce clinical errors (Preece et al., 2009). Incorrectly read, interpreted, or recorded BGL readings Insulin charts differ in the way in which blood glucose levels are presented. Charts

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can display a patient’s blood glucose levels in the form of ‘drawn dot’ graphs, standard tables (with BGL readings recorded across rows or down columns), or in tables with BGL range rows (i.e. graphical displays with numbers instead of drawn dots). Anecdotal evidence (source: task analysis interviews with clinicians) suggests that many clinicians find graphical displays of BGLs inappropriate because they don’t have a fixed time‐axis. For instance, a graph of five BGL readings taken in 15‐minute intervals (i.e. over a 75 minute period), plotted adjacent to a graph of five BGL readings taken in 2‐hour intervals (i.e. over a 10 hour period) could look identical to a rushed clinician who fails to examine the time‐axis values. In terms of graph‐axes, it should also be noted that several charts fail to label y‐axes on the right hand side of the graph area, which could potentially lead to errors in plotting BGL readings close to this axis. Despite clinicians’ preferences for tabular displays (source: task analysis interviews with clinicians), experimental evidence indicates that displaying data in a table can lead to chart users making significantly more errors and taking significantly longer to recognise that a patient is deteriorating compared with graph‐like formats (Horswill et al., 2010), even when the tabular patient data is presented in physiological range rows to resemble a graphical format (Christofidis et al., in preparation –a). Many charts also provide BGL readings to one decimal place (e.g. 4.2), even though clinically relevant differences are only meaningful at the whole number level (e.g. between a reading of 4 mmol/L and 5 mmol/L) (source: task analysis interviews with clinicians). The use of decimal places could potentially inhibit the processing of information, as well as decrease overall legibility (especially on charts with limited writing space). Not noticing ‘abnormal’ BGL readings Targeted glycaemic control in hospitalised patients, the primary objective of diabetic management, appears to vary in priority across insulin charts. The most explicit charts utilise single parameter track and trigger systems; early warning systems that use the routine observation of blood glucose levels (the ‘tracking’) in tandem with established criteria (the ‘triggers’) to prompt standard responses to deteriorating patients. For example, if the blood glucose of a patient receiving subcutaneous insulin rises above 20 mmol/L (hyperglycaemia) or falls below 4 mmol/L (hypoglycaemia), the graph or table draws the user’s attention to the abnormal observation (usually via shaded or coloured ranges). Although an advantage of the single parameter track and trigger system is that it acts to remind the user of the criteria for abnormal blood glucose levels, eliminating the need to memorize this information, many charts don’t provide a clear visual cue when an action is required. Colour cues for instance, may not be salient enough for the user to attend to. In cases where colour cues are overt, the shaded gradients between different ‘triggers’ may be difficult for users to differentiate (especially if the user is colour blind). Other charts only provide target blood glucose ranges, either as part of instructions provided on the chart or

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adjacent to the blood glucose record, requiring the user to mentally compare each observation with the prescribed cut‐off ranges. Hyperglycaemia in particular, can go unnoticed by clinicians (source: task analysis interviews with clinicians). Due in part to the lack of immediate visible patient outcomes (as opposed to hypoglycaemia where patients can lapse into a coma), hyperglycaemic protocol often requires several consecutive BGL readings greater than 12 mmol/L to be reported. It is possible that clinicians aren’t cued effectively by insulin charts to take note of this protocol. Not monitoring BGL frequently enough Implementing insulin therapy in a hospital setting requires frequent and accurate monitoring of a patient’s blood glucose levels. Because no empirical investigation testing the effect of frequency of blood glucose monitoring on the incidence of hyperglycaemia or hypoglycaemia has been conducted, guidelines are limited to expert and consensus opinion. Typically recommended testing frequencies during subcutaneous therapy include at pre‐meals and bedtime for patients who are eating (or every four to six hours for patients who are not eating), and hourly for patients who are subject to continuous intravenous insulin until their blood glucose levels are stable (then every two hours) (Clement et al., 2004). Despite these recommendations, and perhaps in light of the limited empirical evidence to support them, insulin charts vary widely in how frequencies of monitoring blood glucose levels were indicated. Charts can provide users with instructions, tick‐box options to choose from (e.g. hourly or two hourly), or enforce a rigid schedule (e.g., columns or rows corresponding to before and after meals). However some charts provide no indicators, leaving frequency open to clinical judgment and potential error (assuming the guidelines themselves have some clinical validity). Failing to adjust insulin doses There is a divide among some clinicians (source: task analysis interviews with clinicians) as to whether subcutaneous charts require that every dose of insulin be prescribed for every occasion, or whether insulin should only be prescribed once (acting as a standing order) until such time that the dose needs to change. Those in favour of a standing order argue that without it, junior staff (especially over weekends) may neglect to prescribe insulin altogether. Those against a standing order counter argue that a clinician (particularly in hospital units that are not attuned to managing diabetes) may prescribe insulin once, and fail to follow‐up patients’ glucose outcomes and consequently neglect to adjust the order (potentially leading to hypo‐ or hyperglycaemia). This potential error is encouraged by those standing order charts that fail to utilise forcing functions to remind users of necessary follow‐ups. Clinicians similarly disagree over the efficacy of fixed versus flexible dosing schedules used during intravenous infusion insulin therapy (source: task analysis interviews with clinicians). Charts that utilise a fixed schedule provide set infusion rates based on a patient’s BGL range (e.g. if the BGL reading is between 5 and 7 mmol/L, the patient should receive 1 unit/hr of intravenous insulin). However when a patient’s BGL reaches the highest prescribed range, the set infusion rate remains constant until the prescriber returns and writes a revised fixed schedule.

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Thus fixed schedules potentially decrease the likelihood of an adaptive insulin therapy based on a patient’s glucose levels, and increase the likelihood of a patient remaining on a constant and inappropriate rate of insulin. In contrast, variable dosing schedules (which utilise algorithms) provide forcing functions that allow insulin doses to change, by a percentage or proportion, according to patients’ blood glucose levels. Thus both standing order subcutaneous charts and fixed schedule intravenous charts are nurse driven; they rely on treating nurses to contact prescribing medical officers (whilst having to leave patients’ BGLs to deteriorate) to return to the chart and re‐document a new dosage regimen. Clinicians have questioned the appropriateness of leaving this level of responsibility with nursing staff. Incorrectly using telephone orders Most subcutaneous insulin charts include a record for telephone insulin orders, which are used in two situations: (1) if a medical officer requests to be contacted with a patient’s blood glucose level prior to prescribing an insulin dose; or (2) if a patient has been receiving insulin and no dose is ordered. In both instances, the nurse is required to call the treating prescriber to obtain a telephone order for the dose and document that a telephone order has been taken (QH, 2009). Anecdotal evidence (source: task analysis interviews with clinicians) suggests that phone orders for insulin can cause confusion among hospital staff. Often it unclear to users that the phone order record only provides recognition of the order, rather than documents the actual administration of the phone ordered insulin. There is also a concern that the inclusion of telephone orders may encourage a sliding scale approach to insulin prescription, whereby clinicians (especially those not familiar with diabetic management) fail to prescribe regular insulin altogether, and instead make recurring ad‐hoc telephone orders for ‘one‐off’ doses of insulin. Conversely, charts without telephone orders don’t allow nurses to document an unanticipated one‐off dose (e.g. for patients with abnormally high BGLs between meals) when it is clinically necessary. Delaying administration of insulin Ideally, a patient’s insulin will be administered immediately after their BGL reading has been taken. However, anecdotal evidence suggests that there are often significant time lags between the monitoring of a patient’s blood glucose and the subsequent administration of insulin (source: task analysis interviews with clinicians). It is thought that this could be due, in part, to the presentation of blood glucose displays relative to insulin administration records. While several chart designs align these two records so that a blood glucose observation and subsequent insulin administration dose are recorded within the same time‐point column or row, many charts separate the presentations entirely. This means, for example, that the user must document a patient’s blood glucose level at a certain time point in one table and then document the corresponding insulin dose at the same time point in another table. Across insulin charts, these separated records can be adjacent tables on the same page, separate pages of the same chart, or separate charts all together. This separation has the potential to discourage the immediate administration of insulin. Administering an incorrect dose of insulin

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Insulin charts greatly differ in the way in which intravenous and subcutaneous insulin orders are presented, relative to their proximity with insulin administration records. For example, charts can require users to compare insulin orders and administration records over two separate areas of one page, over the front and reverse page of the same chart, and in some cases, over two separate charts (only some of which refer the user to the additional chart). Although subcutaneous charts that utilise correction‐dose insulin to provide real‐time adjustment of insulin dosing are strongly supported by empirical evidence (Hirsch, 2009), because supplemental insulin is not necessary for all patients or necessary at all times, some clinicians have begun to question (source: task analysis interviews with clinicians) whether the position of the record encourages hospital staff to unnecessarily prescribe supplemental insulin. Alternatively, the separation of routine and correction‐dose insulin prescriptions has the potential to encourage a sliding scale approach, where routine insulin is ignored and not administered. The proximity of the correction‐dose order relative to the BGL record also needs consideration. These charts require nurses to, whilst attending to the routine insulin order dose, compare their patient’s current BGL reading with the BGL ranges prescribed in the correction‐dose insulin order, to determine whether a correctional dose (on top of the routine dose) is necessary; a visual cross‐comparison between three sections of a chart(s). If BGL records, insulin orders, and insulin administration records are separated from one another, nurses could potentially administer an incorrect dose of insulin based on the patient’s BGL needs. Not attending to critical instructions Most charts provide general use instructions, guidelines for insulin administration, and protocols for hypoglycaemia and hyperglycaemia management. However across each chart the presentation of this information can come in the form of written paragraphs, bullet points, tables, flow diagrams, or a combination of each. Often time, the important messages within this information aren’t salient enough for the user to attend to. A key example of this (source: task analysis interviews with clinicians) is clinicians’ misuse of intravenous charts for the management of Diabetic Ketoacidosis (DKA); a medical emergency characterized by uncontrolled hyperglycaemia, metabolic acidosis, and increased total body ketone concentration (Escott‐Stump, 2008). Although most charts state that they are not to be used as DKA management tools (and often refer users to a specific DKA protocol), the message is often buried in other (less crucial) information or positioned on a back or outside page. Similarly, for patients receiving intravenous insulin infusion, unopposed insulin administration carries a high risk of severe hypoglycaemia (thus insulin should always be accompanied by a co‐administration of intravenous glucose). Although charts typically provide a written warning that insulin should be given with dextrose, these warnings often aren’t overt enough for the user to notice.

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Appendix E: Usability considerations, customized for insulin charts Category

Usability considerations

• Is non‐safety‐critical information displayed in an unnecessarily prominent way, such that it could potentially draw attention away from safety‐critical information and/or increase visual clutter (e.g. hospital logo or name, administrative codes, etc)?

Page Layout

• Is there a mixture of landscape & portrait‐orientated information that may plausibly reduce readability (e.g. potentially requiring the chart to be turned during use)?

• Is there a missing or ambiguous chart name? • Does the chart fail to organise information in order of importance

(so that attention is naturally drawn to the most important elements first, and the least important elements last)? (E.g. blood glucose level before insulin administration.)

• Are any elements that ought to be perceptually separated not adequately separated (e.g. by a small space or double line)?

• Are headings/labels of the same level of importance formatted differently, potentially providing misleading cues?

• Are any of the boxes for writing something too small (size 14 font is considered to be a minimum handwriting size guideline)?

• Is there an unnecessarily large amount of space devoted to any particular element, potentially introducing unneeded clutter?

• Has the chart failed to take advantage of the potential benefits of using a graph or graph‐like presentation of quantitative data?

Information Layout

• Is basic functionality not understandable intuitively (or with minimal explanation)?

• Is there a problem with compressed font (e.g. Arial narrow) being used anywhere, given this may affect legibility?

• Is the font too small (smaller than 11 point), such that it might impede legibility?

• Is font size potentially giving misleading cues (e.g. important information is in small font and unimportant information in large font)?

Font

• Is capitalization used too often (capitalization is good for highlighting elements but only if used sparingly; also capitalization slows reading)?

• Has the chart failed to use colour where it would have been advantageous to do so (e.g. to draw attention to important elements, to aid perceptual organization, or as part of an alerting system)?

• IF COLOUR IS USED, are the colour shades used inappropriate? For example, if a colour shaded area is to be written on, is the shade sufficiently light ("pastel") for the writing to be clearly visible?

Colour Scheme

• IF COLOUR IS USED, are any of the colours used potentially deceptive in their meaning according to cultural norms (e.g. light

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blue used to indicate "bad"; vivid red used to indicate "no problem")?

• IF COLOUR IS USED AS PART OF A SYSTEM, is there a lack of redundancy for when colours cannot be perceived easily (e.g., colour‐blind users or low‐light conditions)?

• Is information not displayed as a graph or in a graph‐like presentation assuming it was judged that this might reduce errors?

• Does the graph look too small or cramped? • Is the graph label not clear or descriptive? • Is the graph label written vertically with upright letters? • Does the graph label fail to specify units of measurement? • Does the graph label fail to provide an example of how data is to be

recorded (e.g. numeric value, or ●)? • Is the graph label font/formatting exactly the same as the Y‐axis

values font? • Is the vertical axis NOT labelled on the left & right of the page? • Does the scale of Y‐axis values change (e.g. going from .5 intervals

to 1 intervals for the same length of the Y‐axis)? • Are the Y‐axis values not mutually exclusive (e.g. "5‐10", "≤5")? • Are thick vertical lines NOT placed every 3‐4 boxes? • Are the date boxes unnecessarily small (should accommodate size

14 text)?

Recording Blood Glucose Levels

• Are the time boxes unnecessarily small (should accommodate size 14 text)?

• Does the chart fail to include an alerting system where such a system would be of value?

• IF THERE IS AN ALERTING SYSTEM, has the chart failed to make full use of colour to improve its usability?

• IF THERE IS AN ALTERTING SYSTEM, does it involve mentally transcribing information between non‐adjacent areas of the chart (which may increase mental workload and hence the scope for errors)?

• IF THERE IS AN ALTERTING SYSTEM, does it fail to allow for modification for individual patients (e.g., different BGL target range to allow for physiological differences) where modifications may be required?

• IF THERE IS AN ALERTING SYSTEM, is its use less transparent than it could be?

Alerting System (anything that provides cues to the chart user that indicate when something is wrong, e.g., notification of abnormal BGL)

• IF THERE IS AN ALERTING SYSTEM, does the chart fail to include instructions? (Users should ideally not have to refer elsewhere, to minimize errors resulting from inappropriate use.)

• Does the chart fail to include an action system where such a system would be of value?

• IF THERE IS AN ACTION SYSTEM, has the chart failed to make full use of colour to improve its usability?

Action Systems (anything that assists the user to take appropriate critical actions, such as the

• IF THERE IS AN ACTION SYSTEM, does it involve mentally transcribing information between non‐adjacent areas of the chart

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(which may increase mental workload and hence the scope for errors)?

• IF THERE IS AN ACTION SYSTEM, does it fail to allow for modification of relevant values for individual patients (e.g., dosage, frequency of recordings), where modifications may be required?

• IF THERE IS AN ACTION SYSTEM, is its use less transparent than it could be?

frequency of actions, the integration of a recommended dosage schedule, or recommended responses to the output of alerting systems).

• IF THERE IS AN ACTION SYSTEM, does the chart fail to include instructions? (Users should ideally not have to refer elsewhere, to minimize errors resulting from inappropriate use.)

• Is writing required, where a better option might be to provide options to circle or similar (where circling options can reduce cognitive load and minimize handwriting legibility problems and inappropriate entries)?

Does the chart design minimise the user's cognitive load as much as possible? • Does information have to compared or transcribed over non‐

adjacent areas of the same page (potentially requiring users to hold information in memory)?

• Are there any grammatical errors (may impair readability)? • Are there any mis‐spelling or non‐Australian spelling (may impair

readability)? • Are any expressions or instructions less clear and/or more

jargonistic than they could be? • Are any abbreviations or acronyms used unnecessarily (assuming

they may be less transparent than not using the abbreviation or acronym)?

Language

• Could the position of clinicians’ initials required for authorisation cause confusion with close abbreviations or acronyms?

General • Please use this section to provide general comments on chart usability and also address issues that are not covered by any of the design heuristics above

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