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Use of Bayesian Methods for Markov Modelling in Cost Effectiveness Analysis: An application to taxane use in advanced breast cancer. Nicola Cooper, Keith Abrams, Alex Sutton, David Turner, Paul Lambert Department of Epidemiology & Public Health, University of Leicester, UK. OBJECTIVE.
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Use of Bayesian Methods for Markov Modelling in Cost Effectiveness Analysis:An application to taxane use in advanced breast cancer Nicola Cooper, Keith Abrams, Alex Sutton, David Turner, Paul Lambert Department of Epidemiology & Public Health, University of Leicester, UK
OBJECTIVE • To demonstrate how CE decision analysis may be implemented from a Bayesian perspective, using MCMC simulation methods. • Illustrative example:CE analysis of taxane use for the second-line treatment of advanced breast cancer compared to conventional treatment
OUTLINE • Decision-Analytical Model • Transition Probabilities • Model Evaluation Methods • Model Results • Summary & Conclusions
MODEL • 4 Stage stochastic Markov Model • 4 Health states • Response • Stable • Progressive • Death • Cycle length = 3 weeks (35 cycles) • Maximum of 7 treatment sessions
MODEL cont. Stages 1 & 2 (cycles 1 to 3) Treatment cycles Stage 3 (cycles 4 to 7) Stage 4 (cycles 8 to 35) Post -Treatment cycles
TRANSITION PROBABILITIES 1) Pooled estimates • 2) Distribution 4) Application to model 3) Transformation of distribution to transition probability (i) time variables: (ii) prob. variables:
MODEL EVALUATION • Stochastic Markov Models: • Classical Model - Monte Carlo (MC) simulation model (EXCEL) • Bayesian Model - Markov Chain Monte Carlo (MCMC) simulation model (WinBUGS)
RESULTS Docetaxel Death Progressive Respond Doxorubicin Stable
CONCLUSIONS • Advantages of the Bayesian approach compared to equivalent Classical approach • Incorporation of greater parameter uncertainty • Ability to make direct probability statements & thus direct answers to the question of interest • Incorporation of expert opinion either directly or regarding the relative credibility of different data sources
FURTHER WORK • Sensitivity analysis • One / multi-way analysis • Choice of prior distributions • MCMC convergence • Simple versus Complex Markov model • Time dependent variables • Two-way pathways • (e.g. stable to response to stable)