DCAQ, How to…
Kris Wright
Improvement & Support Team
DCAQ – Back to Basics
Demand
• All the requests or referrals from all sources
for a particular service
• Demand CANNOT be calculated based on
past Activity
• Demand can come from the whole (relevant)
population and has NO constraints
(theoretically)
Lessons in Demand
• Demand can be hidden
– Demand for a service that is currently outsourced
is still demand and needs to be counted
– Demand can be inpatient, outpatient, returns and
reviews and again it all needs to be counted
Capacity
• Capacity is the resources available to perform
the work necessary
• Capacity is not simply the number of
appointment slots
• Capacity is finite and is subject to a number of
constraints
Capacity constraints
• Time: there are only 24 hours in a day, and
only 7 days in a week
• Staff: numbers and shifts of staff
• Equipment: number of certain equipment
• Rooms available for running services
• Leave, sickness, study, administration
• All these have to analysed to find the critical
constraint on the service
Activity
• Is all the work done within the service
– Activity is subject to capacity constraints
• Activity does not necessarily reflect capacity or
demand
– April’s activity may be March’s demand
– Problems may arise if you plan April’s capacity and
activity on April’s demand when it is March’s
demand that is being processed
Queue
• The Queue is the previous demand that has
not been processed
• The queue needs to be understood in as much
detail as we understand demand
– It is important to count the patient only once in the
queue, and not repeatedly for all individual steps
within the processes
Demand, Capacity Activity & Queue
Waiting list, queue
Demand
= what we should have done
= All requests
for a service
=
what we should do
Capacity
= what we could do
Activity
= what we did
DCAQ Units
• Units need to be consistent throughout the
data, this can be patients, slots, minutes as
long as D,C,A and Q are all measured in the
SAME unit.
• Units need to be specified clearly, otherwise
false assumptions could be made
DCAQ time units
• Time: however measured, needs to be
consistent.
• The smaller the period of time the more
accurate the analysis can be and the greater
weight can be given to the results
– 7 days can be added to give one week, but one
week cannot be divided by 7 to give 7 days
– Weekly data is the lowest resolution recommended
Detail
• The more detail the better
– As long as it is understandable and consistent
– Data broken down from weeks to days to hours
can be useful and can enable a further level of
analysis
– There is a trade-off when it comes to detail
• Depends on how big the problem is?
• Bigger problems demand more detail to analyse
DCAQ Questions
• Is there a particular area you want to analyse
or a problem you want to address
• Is it prudent to limit the scope of the exercise
and grow it once the analysis is verified
• Can you access the data required historically
for ALL aspects of your service
• Do you have an information contact that can
assist you with data gathering
Questions in Demand
• How can you provide demand data
– Monthly, weekly, daily, hourly
• What is your demand made up of
– New, return, OP, IP, Emergency, paediatric
– Can these be broken down further: urgent, soon,
routine
Identifying your data sources…
PAS
ECG
Physio
Orthotics
Etc.
SCI OP
SCI Gateway
HIS
RIS
PAS
Unisoft
HIS
Audiology
Labs
COMPAS
Questions in Capacity
•
•
•
•
How many sites does the service encompass
How many consultants/staff are involved
Hours, type, and allocation of appointments
How many pieces of key equipment/rooms are
there
• Think about limiting the scope initially
Questions in Activity
• How can you provide activity data?
– Monthly, weekly, daily, hourly
• What is your activity made up of?
– New, return, OP, IP, Emergency, paediatric
– Can these be broken down further: urgent, soon,
routine
• Are these categories different from the
demand categories…problems
Questions in the Queue
• How can you provide queue snapshots
– Monthly, weekly, daily
• What is your queue made up of
– New, return, OP, IP, Emergency, paediatric
– Can these be broken down further: urgent, soon,
routine
– What about the un-triaged queue
• Are these categories different from the
demand/activity categories…problems?
DCAQ interactions
D
D
D
QD
Plan capacity from
known demand
Waiting time
C
C
C
A
A
A
QD
QD
DCAQ
Exercises
DCAQ Exercise
•
•
•
•
Demand
Capacity
Activity
Queue
= 20 patients
= 18 patients
= 15 patients
= ???
• Demand – Activity = Queue
• Capacity – Activity = Under/Over Utilisation
If average Demand = average Capacity,
variation mismatch = queue
Queue
Capacity
Demand
Can’t pass
unused capacity
forward
time
Capacity Exercise
• You have been given patient demand for 12
weeks: the maximum demand is 10 and the
clinic capacity is 11 each day.
• Is there a capacity problem here?
• There is a problem within this clinic…Why?
Optimum Capacity
• Optimum capacity is a figure of capacity
designed to cope with the variation in demand
• Optimum capacity is calculated from demand
data using the formula below
• optimum capacity = min demand + ( 0.8
(max demand – min demand ) )
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Number of Referrals
SPC - X Chart Weekly Demand Identifying Optimum Capacity
160
140
120
100
80
60
Demand
Mean
UCL
LCL
Optimum Capacity*
40
20
0
Week
* Optimum Capacity = minimum demand + 80% of variation in demand
Demand and Optimum Capacity
• You have been given two strings of weekly
demand data, find the optimum capacity figure
for both strings.
• Look at the average demand figures for both
strings, what does this tell us about variation
and the impact on optimum capacity?
• What about the Queue? … Prizes?
Queue and Capacity
• When the capacity is set at the value of average demand the
queue builds rapidly
Resultant Queue, Capacity Set at Average Demand
50
45
Demand/Capacity/Queue Number
40
35
30
Demand
Cumulative Queue
Capacity Set
25
20
15
10
5
0
1
2
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Week Number
7
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10
Queue and Capacity
• When the capacity is set at the value of “optimum capacity” the queue
can be maintained more effectively
Resultant Queue, Capacity Set at "Optimum Capacity"
50
45
Demand/Capacity/Queue Number
40
35
30
Demand
Cumulative Queue
Capacity Set
25
20
15
10
5
0
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Week Number
7
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10
Exercise
• Key question exercise
• From the information given what questions
would you ask about the data and the service
purely from a DCAQ perspective?
DCAQ Questions – ‘Back to Basics’
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•
•
•
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What is the problem?
Understand your service’s D,C,A & Q
Measure your service’s D,C,A & Q
Understand the interaction of D,C,A & Q
Identify resources (i.e. staff) to assist with:
– Gathering, analysing and interpreting the data