michael s. kerr, phd school of nursing, university of western ontario and scientist, workplace...

Michael S. Kerr, PhD

School of Nursing, University of Western Ontario

and

Scientist, Workplace Studies Area,Institute for Work & Health

Toronto, Ontario

N318b Winter 2002 Nursing Statistics

Nur 318b 2002 Lecture 1: page 2

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Institute for Work & Health

IntroductionBackground:MSc and PhD in epidemiology

Research interests include:- occupational epidemiology- work stress- biomarkers- health services research

What is the “Institute for Work & Health”?


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Today’s Class(es) Overview of the course Why take a statistics course?

- a quick look at some real data<< 10 min break >>

First lecture:Levels of measurement, hypotheses and types of variables

Group work: hypotheses and levels of measurement

Followed by small groups from 12-2 PM


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Course FacultyProfessorProfessor:: Mickey Kerr Mickey Kerr

OfficeOffice: H28: H28 PhonePhone: 661-2111 Ext. 86580: 661-2111 Ext. 86580Office HoursOffice Hours: : Wednesdays 1030-1200, 1300-1400Wednesdays 1030-1200, 1300-1400or by appointmentor by appointmente-mail ([email protected]) or phone my officee-mail ([email protected]) or phone my office

Teaching AssistantsTeaching Assistants:: Kristen Lethbridge, Heidi Siu Kristen Lethbridge, Heidi Siu OfficesOffices: H035, H021: H035, H021

Office HoursOffice Hours: : Tuesdays after class 1400-1600 (KL) Tuesdays after class 1400-1600 (KL) Mondays 1500-1700 (HS)Mondays 1500-1700 (HS)


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Text:Text:

Munro, B. H. (2001). Munro, B. H. (2001). Statistical methods Statistical methods for health care researchfor health care research. .

(4th Ed). Philadelphia: Lippincott. 2001(4th Ed). Philadelphia: Lippincott. 2001

Course syllabus:Course syllabus:

- available from UWO Bookstore (#M4476)- available from UWO Bookstore (#M4476)

- contains lecture outlines, required - contains lecture outlines, required readings and questions for weekly readings and questions for weekly assignmentsassignments

Course Supplies


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Course Description

1.1. an introduction to basic statisticsan introduction to basic statistics2.2. goal is for students to develop an goal is for students to develop an

understanding of statistical concepts understanding of statistical concepts and findings in and findings in researchresearch articles. articles.

3.3. builds upon Nursing 319a course - builds upon Nursing 319a course - ResearchResearch Methodology Methodology

4.4. develop critical analysis skills to enable develop critical analysis skills to enable integration of integration of researchresearch into practice into practice


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i) Lectures

Large Class:Large Class:Tuesdays: 2 hours from 1000 - 1200 Tuesdays: 2 hours from 1000 - 1200 in in MS 341MS 341

Content:Content:1. discussion to clarify what was read in text 1. discussion to clarify what was read in text and prepared for classand prepared for class2. review of data analyzed using the "test of 2. review of data analyzed using the "test of the week"the week"3. direction for small working group (i.e. the 3. direction for small working group (i.e. the weekly assignment) and next classweekly assignment) and next class


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ii) Small groupsTime and Locations:Time and Locations: Tuesdays following class: 2 hours from 1200-1400 Tuesdays following class: 2 hours from 1200-1400 in rooms H018, H19, and H9, (MS016, MS017), MS018, in rooms H018, H19, and H9, (MS016, MS017), MS018, MS022, MS023, MS027, MS028, MS029. MS022, MS023, MS027, MS028, MS029. - course faculty available for consultationcourse faculty available for consultation- focus is on collaborative learning activities such as:focus is on collaborative learning activities such as:1. weekly critique of results sections of specific studies 1. weekly critique of results sections of specific studies highlighting the "test of the week"highlighting the "test of the week"2. time with your group to work on 2. time with your group to work on group assignmentsgroup assignments. . Group MembershipGroup Membership:: Self-selected groups of approximately 7-9 studentsSelf-selected groups of approximately 7-9 students

Don’t take these sessions for granted as they are important opportunities to test knowledge – they will help with the exam !


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At the beginning of each week select:At the beginning of each week select:1. 1. Group leaderGroup leader - who is responsible for facilitating discussion - who is responsible for facilitating discussion and decision making, andand decision making, and2. 2. RecorderRecorder - who is responsible for writing answers to the - who is responsible for writing answers to the learning activity and ensuring all participating students sign the learning activity and ensuring all participating students sign the cover page; and,cover page; and,3. 3. An observerAn observer - who is responsible for noting involvement of - who is responsible for noting involvement of group members and encouraging those who are not group members and encouraging those who are not participating to do so. participating to do so. Rotate who has each of the three roles each week over the Rotate who has each of the three roles each week over the course so that each group members assumes all of the rolescourse so that each group members assumes all of the roles

Please don’t take these sessions for granted as they are important opportunities to test knowledge – they will help with the exam !

Suggested Format for Small Working GroupsSuggested Format for Small Working Groups


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The final paper is due by 1600 Thursday, April 11, 2002. The final paper is due by 1600 Thursday, April 11, 2002. Note, extensions will Note, extensions will NOTNOT be granted on the date the be granted on the date the final paper is due. final paper is due. A Request for Extension Form must be A Request for Extension Form must be completed and will be kept on the student’s academic completed and will be kept on the student’s academic record. 5% will be deducted from the paper for every day it record. 5% will be deducted from the paper for every day it is late. Also, please remember that unless an idea or is late. Also, please remember that unless an idea or thought is originally yours, credit must be given to the thought is originally yours, credit must be given to the author. author.

For weekly assignments, please include a title page with: For weekly assignments, please include a title page with:

1) your group name; 2) the names of all group members 1) your group name; 2) the names of all group members printed; 3) signatures of all group members present for the printed; 3) signatures of all group members present for the group work that day; 4) the date; and 5) topic of the group work that day; 4) the date; and 5) topic of the assignment. assignment. For group assignments, only those present For group assignments, only those present and signing cover sheet will get a mark.and signing cover sheet will get a mark.

Review the conditions applicable to Review the conditions applicable to ALLALL written assignments: written assignments:


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iii) Exams

Mid-term ExamMid-term Exam:: March 12, 2002 during class time (25%)March 12, 2002 during class time (25%)This 2.5-hour, open-book exam will take place during class time in This 2.5-hour, open-book exam will take place during class time in Rooms DS3008 and another TBA. The format will include multiple Rooms DS3008 and another TBA. The format will include multiple choice and short answer questions. You may bring texts and notes choice and short answer questions. You may bring texts and notes to the exam for your use. to the exam for your use.

Final Examination:Final Examination: Date: April 17th Place: TBA (30%) Date: April 17th Place: TBA (30%) This 3-hour, open-book exam will take place as determined by final This 3-hour, open-book exam will take place as determined by final exam timetable. Exam format is multiple choice and short answer. exam timetable. Exam format is multiple choice and short answer. You may bring texts and notes to the exam for your use. You may bring texts and notes to the exam for your use.


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iv) Research paperDue: Thursday April 11, 2002 by 1600 hrs.Due: Thursday April 11, 2002 by 1600 hrs.Members of the small working groups are to form subgroups of Members of the small working groups are to form subgroups of two to four students per subgroup. The purpose of the 10 page two to four students per subgroup. The purpose of the 10 page paper is to critique the results and interpretation of results paper is to critique the results and interpretation of results reported in one (1) research article. The research articles are in reported in one (1) research article. The research articles are in the course syllabus. Chose the course syllabus. Chose one (1) of eitherone (1) of either:: A)A) Hayman, L. L., Meininger, J. C., Coates, P. M., & Gallagher, Hayman, L. L., Meininger, J. C., Coates, P. M., & Gallagher, P. R. (1995). Nongenetic influences of obesity on risk factors for P. R. (1995). Nongenetic influences of obesity on risk factors for cardiovascular disease during two phase of development. cardiovascular disease during two phase of development. Nursing ResearchNursing Research, , 4444, 277-283., 277-283.ORORB)B) Gross, D., Rocissano, L., and Roncoli, M. (1989). Maternal Gross, D., Rocissano, L., and Roncoli, M. (1989). Maternal confidence during Toddlerhood: Comparing preterm and fullterm confidence during Toddlerhood: Comparing preterm and fullterm groups. groups. Research in Nursing and HealthResearch in Nursing and Health, , 1212(1) 1-9(1) 1-9

Please review the details on p5 of syllabus


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v) Research practice research experience and follow-up paper may be chosen in research experience and follow-up paper may be chosen in

lieu of the final statistics paper. lieu of the final statistics paper. please review please review eligibility criteriaeligibility criteria in the syllabus (p 6) in the syllabus (p 6) includes 25 hours of work on a faculty research projectincludes 25 hours of work on a faculty research project multi-faceted evaluation includes a short experiential paper multi-faceted evaluation includes a short experiential paper

students to be randomly selected for the experience via students to be randomly selected for the experience via sign-up sheet posted on the N318 bulletin board sign-up sheet posted on the N318 bulletin board priorprior to the to the class on class on January 22, 2002January 22, 2002. .

appropriate forms will be provided to participating students appropriate forms will be provided to participating students at the end of the third class at the end of the third class (January 23, 2002)(January 23, 2002). .

students expected to contact the appropriate faculty students expected to contact the appropriate faculty member by member by Friday January 25, 2002Friday January 25, 2002 to set up practicum to set up practicum

Please note date changes w.r.t. syllabus


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Course Evaluation SummaryAssignmentAssignment Date DueDate Due Percent of Percent of

Full GradeFull Grade

Completed in Small GroupsCompleted in Small Groups Weekly group assignmentsWeekly group assignments Each Tuesday Each Tuesday

after groupsafter groups 15%15%

Completed in Sub-GroupsCompleted in Sub-Groups

(2 -4 members of work groups) (2 -4 members of work groups) Research PaperResearch Paper (no practicum) (no practicum)

OROR

Research Practice Experience and Research Practice Experience and PaperPaper (completed individually) (completed individually)

Thursday, April Thursday, April 11, 200211, 2002

Winter term Winter term

Paper - Thursday, Paper - Thursday, April 11, 2002April 11, 2002

30%30%

research research andand paper combinedpaper combined

30%30%

Completed IndividuallyCompleted IndividuallyMid term Exam (2.5 hrs)Mid term Exam (2.5 hrs)

Final Exam (3 hrs)Final Exam (3 hrs)

March 12/02 in March 12/02 in class, open bookclass, open book

April 17, 2-5 PM April 17, 2-5 PM Place TBAPlace TBA

25%25%

30%30%


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Why Do Nurses Need a Statistics Course?

1.1. statistics provide scientific foundation in a statistics provide scientific foundation in a constantly evolving constantly evolving professionalprofessional practice practice

2.2. shift to evidence-based practice means more shift to evidence-based practice means more nurses will need to research in practice nurses will need to research in practice

3.3. need to understand why and how certain need to understand why and how certain statistics are generated to critically appraise statistics are generated to critically appraise what researchers present to youwhat researchers present to you

4.4. course will equip you with a solid statistical course will equip you with a solid statistical foundation that will in turn help you cope with foundation that will in turn help you cope with the data “mountain” the data “mountain”


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What is the health status of acute care hospital RN’s?

Presented to CFNU Board of Directors in early 2001

A “Real-World” Example for the Use of Statistics in Nursing

While viewing slides, think of issues you might like to discuss in more detail – i.e. are these data convincing or not?


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Ontario Nurse Survey

About 15,000 nurses sent surveys (via CNO) About 58% response (N=8,141) Targeted to medical/surgical wards All acute care hospitals in Ontario (up to 100

nurses sampled) Included Siegrist’s ERI scale and MSK pain items

Mailed survey of registered nurses in acute care, non-specialty hospitals in Ontario (part of a 5-country study)


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Siegrist’s Effort-Reward Imbalance (ERI) Model

efforts

demandspressures

responsibilities

rewards

salarysupportrespect

e.g. prospective German cohort study found ERI a key factor for IHD rates in blue collar workers


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Burnout

• almost 4 in 10 report high burnout (EE sub-scale)• may be “internalizing” work stress?

38.1

20.4

13.2

0

10

20

30

40

EmotionalExhaustion

PersonalAccomplishment

Depersonalization

Percent


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Back / Neck Pain in Last Week

30.825.3

43.9

0

10

20

30

40

50

Pain status

None/Low

Moderate

High

Percent

Back and/or neck pain frequency in past week

• 1 in 4 nurses have pain most or all of the time


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Percent

• poor work environment a driver of burnout?

(Note: Percentages do not add to 100% since they are not cumulative.)

Are Burnout and ERI Scores Related?

13.2

31.7

65.7

010203040506070

None

Moderate

High

Burnout status

% ERI present in each pain group

None Mod High

% with ERI


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29.1

40.3

55.8

0

10

20

30

40

50

60

% ERI present in each pain group

None/Low

Moderate

High

MSK pain status

Percent

• poor work environment a driver of pain?


Are MSK Pain and ERI Scores Related?

None Mod High

% with ERI


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Main Conclusions Nurses report high rates of back/neck pain and

burnout (emotional exhaustion only, not personal accomplishment or depersonalization)

The workplace psychosocial environment is strongly associated with the health of the nurses (physical demands also important though!)


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How easy was it to follow the presentation of these data? Any questions?

The main aim of the course is to make this type of thing easier for you to understand and even be able to present on your own !!

Data Summary


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10 minute break !


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Lecture 1: Measurement Scales,

Types of Variables and

Hypotheses


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N318bStatistics

N319aResearchMethods

The Research Process

Identify the Problem

Develop a study protocol

Collect the data

Draw inferences

Analyze the data

(For Quantitative Studies)


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Some Background Terms

Descriptive statistics: – for summarizing or describing a sample Inferential statistics: – for making inferences (conclusions) or to generalize from a sample to a population

Sample – part of a population and what you will use in almost all studiesPopulation – all members of a particular group of interest


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for research, focus is on inferential statistics

WHY? reliability and validity of inference depends on

quality of sample good statistics can’t save a bad study !

Statistics is largely about quantifying the probability of error when making a generalization

from a study sample to a population

A Few Key Points


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Measurement ScalesNominal data: – distinct, unordered, qualitativee.g. gender, race, others?Ordinal data: – ordered, distinct, qualitative categories e.g. health status, SES, others?Interval data:– ordered, quantitative categories,known intervalse.g. can be continuous (e.g. F temp) or discrete (e.g. parity), others?Ratio data:– most precise metric due to useful zero valuee.g. BP, weight, height, others?


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Scale Mutually exclusive categories

Categories have order

Standard unit of measure

Useful zero point on scale

Nominal X

Ordinal X X

Interval X X X

Ratio X X X X

Summarizing the Scales

(N.O.I.R)


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Some Caveats on Scales

Nominal data analysis can be more limited (e.g. counts or frequencies only)

Ordinal “should”have same limitation but often treated like a continuous scale

Interval and Ratio data often “collapsed” to an ordinal or even nominal scale

(threshold value?)

(loss of information, restricts analysis)

Why?

What is the main problem with doing this?


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Types of Variables

Independent: (exposure)– typically the variable(s) manipulated, controlled (or at least recorded) by the researchere.g. dietary interventions, others?Dependent: (outcome)– typically the main variable of interest being measured by the researchere.g. weight loss, others?

Study conducted comparing effect of two dietary interventions on weight loss in obese children

Scenario


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Types of Hypotheses - 1

Null hypothesis (H0): - proposes no difference or relationship between variables of interest (basis for statistical inference)e.g. There is no difference in weight loss between the two dietary intervention groups.Research hypothesis (Hr): - opposite of the null hypothesis (i.e. states that there is a relationship between variables)- also called alternative hypothesis or Ha

e.g. There is a difference in weight loss between the two dietary intervention groups

Two sides of the same coin !


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Directional hypothesis: - proposes a specific direction for effecte.g. Intervention A will reduce weight more effectively than Intervention BNon-directional hypothesis: - no specific direction but an effect is predicted e.g. Intervention A and B will differ in their ability to induce weight loss


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Causal hypothesis: - implies that a stated variable is responsible for any observed effect- e.g. Intervention A will induce greater weight loss in obese children than Intervention BAssociative hypothesis: - proposes no specific direction for effecte.g. Dietary intervention may lead to weight loss in obese children


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Simple hypothesis: - typically involves a cause-effect relationship only between dependent and independent variables- e.g. Intervention A will induce weight loss in obese children Complex hypothesis: - typically involves more complicated causal pathway between multiple variables - e.g. Intervention A will induce weight loss in obese children who have a family history of obesity


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Summarizing Hypotheses Null or Research? Directional or Non-directional? Causal or Associative? Simple or Complex?

The 4 categories are not mutually exclusive – i.e. hypotheses can be categorized using all 4 levels

e.g. Dietary intervention A will induce more weight loss than dietary intervention B in obese children

Research Directional Causal Simple


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Next Week - Lecture 2: Measures of Central

Tendency and VariabilityFor next week’s class please review:1. Page 12 in syllabus2. Textbook Chapter 1, pages 8-233. Textbook Chapter 2, pages 29-444. Syllabus papers:

i) Arathuzik (1994) ii) Hayman et al. (1995)


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Workshop Rooms:

H018, H19 and H9

(MS016, MS017)*, MS018, MS022MS023, MS027, MS028, and MS029

Please go to one of these rooms with your group from last term or join one


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Frequency of Illness Absence in Past 90 Days

Percent

• almost half missed at least one shift due to illness

28

11.6

53.6

6.8

0

10

20

30

40

50

60

Days absent

None1 day2 days>= 3 days

Illness absence in past 90 days

0 1 2 >= 3


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Are MSK Pain and General Health Scores Related?

• MSK pain a driver for overall health scores?

26.538.5

81.5

14.6

57

0

20

40

60

80

100

Health Category

Excellent Very good Good Fair Poor

General health group


Percent

% with HIGH pain level


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Overview of the Course1. Course Faculty2. Course Supplies3. Course Description4. Ends-in-View (objectives)5. Process – lectures, work groups,

exams, research paper and research practice

6. Course Evaluation7. Course Content

michael s. kerr, phd school of nursing, university of western ontario and scientist, workplace...

Documents

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