decision modeling techniques

Download Decision Modeling Techniques

Post on 12-Jan-2016

42 views

Category:

Documents

0 download

Embed Size (px)

DESCRIPTION

Decision Modeling Techniques. HINF 371 - Medical Methodologies Session 3. Objective. To review decision modeling techniques and discuss their use in healthcare decision making. Reading. - PowerPoint PPT Presentation

TRANSCRIPT

  • Decision Modeling TechniquesHINF 371 - Medical MethodologiesSession 3

  • Objective To review decision modeling techniques and discuss their use in healthcare decision making

  • ReadingRoberts M S and Sonnenberg F A (2000) Chapter 2: Decision Modeling Techniques, in Chapman G B and Sonnenberg F A (eds) Decision Making In Health Care: Theory, Psychology and Applications, Cambridge University Press, USA,

  • Evidence PreparationEngine where data is translated into information

  • Why do we need them?To create a quantitative representation of clinical choicesTo compare alternatives and results of choicesTo integrate data from various sources to describe a clinical situationTo simulate trial results to the whole population

  • Requirements for a Decision ModelPerspective: identification of whose perspective has been used to develop the modelContext: who is involved, what conditions, what interventionsComplexity (or granularity): what should be the level of detailTime horizon

  • Simple Decision TreeValue 1 (U1)Value 2 (U2)Value 3 (U3)Value 4 (U4)Outcome 1Outcome 2Outcome 3Outcome 4p1p2p3Choice 1Choice 2Total = 1Decision NodeChance Nodep4

  • TerminologySensitivitySpecificityTrue PositiveFalse PositiveFalse NegativeTrue Negative

  • ExampleLE Late RxLEHIV+HIV-ScreenNo Screenp5p640.3 QALYs40.3 QALYs3.5 QALYs39.4 QALYs2.75 QALYs2.75 QALYs0.99880.00120.48560.51440.50.539.20503.544421.525021.8921.53

  • Influence DiagramsScreen for HIVYes/NoTreat for HIVYes/NoTest ResultHIVStatusLife Expec

  • Sensitivity Analysis

  • Markov ProcessesIterative in time, can be repeated until everybody in the absorbing stateBased on the probabilities of change in statusThree statesRecurrent stateTransient stateAbsorbing state

  • Markov Processesp4HIV+AIDSDEADHIV+AIDSDEADAIDSDEADDEADp1p2p3p4p5P6

  • LE Late RxLEHIV+HIV-ScreenNo Screenp5p6HIV-DEADHIV-DEADHIV-DEAD

  • Alternatives to Markov ProcessesMarkov Processes has no memory and based on discrete snapshots in timeSemi Markov Processes time is continuous, one does not move to the next another stage in the next term and measures holding timesIndividual Simulations as a solution: simulates individuals travelDynamic influence diagrams creates a new influence diagram for the next cycleDiscrete event simulation: what is possible to do