Term

Definition
 formulate & build a qualitative model to address a decision making problem in managing community HCP
 simplify and refine the model structure
 id and gather relevant data
 build a spreadsheet model
 use the model to predict the impact of different options in terms of the number of lives saved
 carry out a sensitivity analyses
 evaluate the model



Term
Step1:Draw up an initial graphic model 

Definition
Think about what managers are trying to achieve &what the model needs to predict
1. drawing an influence diagram showing relevant factors for one disease.
2.start with your outcome variable pn the right of sheet of paper and work upstream to the left.
3.identify direct or "proximal influences (PIs)" then more distal factors that affect PIs.
4. id control variables
5. define treatment impact factor



Term
Step3: Refine the graphic Model 

Definition
Refine model in light of what has been learned about the system and any concerns raised so far;
 leave factors out that are expected to be unchanged over model's time scale
 Add more detail: variable costs (incr trx volumes lowers cost/pt) & fixed costs.
 forecast how exogenous variables will vary
 include how the balance of numbers of lives saves with different numbers treated
 derive a formulae of how outcome variable calculated from control/exogenous variable



Term
Step3: Identify and gather relevant data 

Definition
 data on treated and untreated mortality (studies in literature)
 data on variable and fixed costs (local information)
 think about the data's reliability and whether a sensitivity analysis is needed
 improve model by repeating model dvt cycle;i.e. reexamining your theory and cillecting new data



Term
Step 5: use model yo decide on the strategic balance 

Definition


Term
Step 6: carry out a sensitivity analyses (SA) 

Definition
 trying different values of the parameters to se how much they alter yiur conclusions
 investigates the effects of error in the data and changes in the underlying assumptions on the results.
 multiple criteria and judgement;
 one objective thus no judgement involved
 In reality more objectives (e.g. improve sx) and equity issues
 thus, best option will be a matter of opinion thru "consensus" e.g weightavoiding death vs any other benefits from trx.
 when >1 criterion no objectively best option unless; one option is equal to or better than ALL the others on ALL criteria



Term
Step 7: evaluate the model 

Definition
 transparency: simple spreadsheet allow managers to examine formulae and test modeli.e. assess face validity
 predictive validation: to a degree as results can be tested for plausibilirt (whether they are in the right kind of range) but not for correctness (i.e. case fatality rates)
 accreditation: models published in scientific literature should have been subject to peer review . Publication: corroboration btw differ models =incr confidence
Cl: 1st series of cycles of DM; unable to use model validated against empirical data in local context. Thus rely on 1/consensus, 2/internal logic/3 data from elsewhere. 

