Simulation for Strategic Planning – the ScenarioPlanning the Scenario GeneratorPopulation Analysis Eventp yMarch 2009

Si l ti Vi t l P l tiSimulating a Virtual Population

Scenario Generator• Simulating a virtual population and disease g

related demand• Through care pathways• To understand the impact of population and

disease, and likely changes to the healthcare environment on expected activityenvironment on expected activity

• To test “what if” scenarios

What is Simulation?

A technique that aims to imitate abstract andA technique that aims to imitate, abstract and represent a system, process or behaviour for specific analytical, decision support or learning purposes

Simulation for strategic planning

Will it work?it’s too risky to test live Will it impact

elsewhere in t

How might demand

our systemchange over time?

What is the optimum cost

/ capacity trade off?

Modelof

care trade-off?care

Why simulate?

• It can help to take you beyond a process map into potential impacts of implementation

• It aids understanding of complex systems• You might discover unanticipated consequences of a plan• It should help to inform decisions

BUT• Simulation won’t tell you the answer, but it will help you ask

better questions• It will only be as good as the data you put in, but it will help

you make sense of that data• All models are wrong but some are useful• All models are wrong, but some are useful• It will not be an accurate predictor of events, but it might be

better to be “broadly right than precisely wrong”y g y g

Objectives of the ScenarioObjectives of the Scenario Generator

The ability to model scenarios based upon local population,The ability to model scenarios based upon local population,prevalence of disease and pathways of care, and to simulate their operation to:make more informed strategic decisions and planning choicesoptimise throughput, end-to-end transaction time, cost reduction and

ili iresource utilisationanticipate effects that changes to a particular model of care might

have upon a whole healthcare system and that might otherwise havehave upon a whole healthcare system and that might otherwise have been overlookedbetter understand the response of the health system to changes inbetter understand the response of the health system to changes in

population, disease prevalence, service capacity, configuration and demand

Functional model

Scenarios

PopulationDemographyPrevalence

Events

ScenariosReferral patternsCapacityDurationEvents

Mental Health

Duration

Population

Wholesystemmodel

Simulationresults

Urgent

Planned

Demographicweighting

MaternityPrevalence

Service points flows Pathway Constrainedpoints, flows

& waitsy

models resources

A C P h i S iA Care Pathway in Scenario Generator

Lambeth PopulationLambeth Population

Simulating Population Growth

• Scenarios can be modelled for population growthp p g• SG ages the population year on year adding births and taking away

deathsP j ti f ti ll i d i ti t b d ll d i• Projections function allows inward migration to be modelled in addition to natural population growth

• Changes to the health system care pathways can be modelled withinChanges to the health system care pathways can be modelled within same scenarios

• ….any number of “what if” scenarios

Lambeth Population Forecast –Population x prevalence + birthsPopulation x prevalence + births ‐ deaths

1 year run producing1 year run, producingactivity data

5 year run looking at possible growth in urgent admissions 

What if Scenario

• 7% less primary care activity referred to7% less primary care activity referred to outpatients in year 2

• New population of 5000 arrives in year 3y

Baseline Scenario:Lambeth – 5 year forecastforecast

What if Scenario:Lambeth – 5 yearLambeth  5 year forecast

Primary Care DemandyLambeth – 5 year forecast

Costs Lambeth – 5 f tyear forecast

Results

• Simulation runs of up to 50 yearsSimulation runs of up to 50 years• Activity by step and across pathways (high level display) • CostsCosts• Constraints (queuing) overall and at multiple points in run• Waiting standard facility and breach reportingg y p g

Where is it being used?

Current uses…

The resource impact and capacity requirements of new models of care:

• population growth

t ti it l• testing capacity plans

• viability of existing hospital services as a result of shift to iprimary care

• care pathways (incl. falls, stroke, major trauma)

• remodelling unscheduled care

• admission avoidance/intermediate care• admission avoidance/intermediate care

• polyclinics

Link to Spatial Implications

• SG results expressed in terms of activity by individual pathway p y y p ysteps, and aggregated steps and costs (with inflation)

• Users need to be able to translate this into potential requirement for estates and workforceestates and workforce

• Currently developing work with UEL and HUDU to understand results in terms of spatial requirements

Define

Designinitial

Defineproblem

initialmodel

Selectapproaches

ValidateDevelopconcept Validateconcept

Doanalys

esDo otheranalyses

SimulateRefine

es

Consult

Drawconclusions

Act upon

outputsoutputs