Optimising existing services -

Understanding Capacity, Demand and Flow

Lesley Wright – Quality Improvement Consultant

Approaches to optimising services

3 key activities:

• Understand capacity, demand and flow

• Improve data quality

• Maximise capacity

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85% of the reasons for failure to meet customer expectations are related to

deficiencies in systems and process rather than the employee. The role of

management is to change the process rather than badgering individuals to do

better”

“ If I had to reduce my message for management to just a few words, I’d say it

all had to do with reducing variation” – W Edwards Deming

‘Foster wholeheartedly the growth and development of all staff, including

their ability and support to improve the processes in which they work’

A promise to learn a commitment to Act:

- Prof. Don Berwick – President , Founder IHI

Understanding Capacity, Demand: definitions

Capacity: Resources available to do the work.

Equipment (kit) AND the skill (people) to do the work.

Measure: multiply number of pieces of kit (rooms) and staff available to do procedure in minutes. e.g.

2 CT scanners staffed 9am – 5pm (8 hours) = 960 minutes of capacity per day

Demand: Work you are requested to do.

All the requests / referrals coming from ALL sources.

Measure: multiply number of patient requests/referrals by the time in minutes to do procedure

Timings: from the patient entering the examination room to leaving (80% of the time)

20 referrals x 15 minutes (time to perform procedure) = 300 minutes demand

NB. Measuring appointment time will over estimate demand.

20 referrals given a 20 minute scheduled appointment = 400 minutes demand

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Understanding Capacity, Demand: definitions (2)

Activity: Work carried out by staff.

Measure: Multiply number of patient requests/referrals by the time in minutes to do procedure.

Timings: from the patient entering the examination room to leaving (80% of the time)

Activity should be measured in same time allocations as demand

1 X15 minutes demand = 1 x 15 minute activity

Backlog: WL: – what you should have done.

Backlog is the demand not dealt with because all appointments are taken. With enough capacity they would have been seen.

Measure: Multiply number of patient requests/referrals by the time in minutes it takes to do procedure.

20 referrals waiting x 15 minutes (time taken to perform procedure) = 300 minutes WL/backlog

Planned waits/ deferred demand: are requests that MUST be included in backlog as they

will become demand and require capacity

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Activity is NOT demand

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Source: Imaging & Oncology 2016

Improving data quality

Why is good data important

• Operational management

• Business case development

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Vitals Flow Charts ©

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Vitlal's Charts for St Elsewhere's Endoscopy Deoartment

demand activity WiP = cumulative diff

WIPDemand and activity

© Slide courtesy Dr. Kate Silvester www.improvementscience.net

Collect: All patients requested after beginning 19/01/15

Examined before end 18/01/16

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Conventional intuitive way request data

Information window 19th Jan 2015 – 18th Jan 2016

© Slide courtesy www.improvementscience.net

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Activity, Demand &WIP

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Demand, Activity & WIP: CT Jan 2015

Daily demand Daily activity Cumm. Diff. betw. Demand and activity (WIP)

Incorrect (intuitive) data collection

Data Window19/01/2014 01/11/2016

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Correct way: Counter-intuitive request

and examined after 19/01/15All patients requested before end 18/01/16

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Information window 19th Jan 2015 – 18th Jan 2016

Correct way: Counter-intuitive request

© Slide courtesy www.improvementscience.net

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Include:

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CT: Demand, Activity & WIP - 19th Jan 2015 - 18th Jan 2016

demand activity Cumm. Diff. betw. Demand and activity (WIP)

Correct (counterintuitive data collection)

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Days CT; Request - Exam wc 19th Jan - 31st Jan 2015

BaseLine 1.20.010

Understanding Flow - Impact of ‘carve out’ on capacity

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• Balanced Capacity & Demand will not be sufficient if ‘carve out’ slots or sessions www.steyn.org.uk/

Impact of ‘carve out’ simulation

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For model go to www.steyn.org.uk/models/demand analysis.xls