, Volume 26, Issue 8, pp 633–648 | Cite as

Modelling Approaches

The Case of Schizophrenia
  • Bart M. S. HeegEmail author
  • Joep Damen
  • Erik Buskens
  • Sue Caleo
  • Frank de Charro
  • Ben A. van Hout
Current Opinion


Schizophrenia is a chronic disease characterized by periods of relative stability interrupted by acute episodes (or relapses). The course of the disease may vary considerably between patients. Patient histories show considerable inter- and even intra-individual variability. We provide a critical assessment of the advantages and disadvantages of three modelling techniques that have been used in schizophrenia: decision trees, (cohort and micro-simulation) Markov models and discrete event simulation models. These modelling techniques are compared in terms of building time, data requirements, medico-scientific experience, simulation time, clinical representation, and their ability to deal with patient heterogeneity, the timing of events, prior events, patient interaction, interaction between covariates and variability (first-order uncertainty).

We note that, depending on the research question, the optimal modelling approach should be selected based on the expected differences between the comparators, the number of co-variates, the number of patient subgroups, the interactions between co-variates, and simulation time. Finally, it is argued that in case micro-simulation is required for the cost-effectiveness analysis of schizophrenia treatments, a discrete event simulation model is best suited to accurately capture all of the relevant interdependencies in this chronic, highly heterogeneous disease with limited long-term follow-up data.


Schizophrenia Markov Model Discrete Event Simulation Probabilistic Sensitivity Analysis Cohort Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Johnson & Johnson provided funding to Pharmerit BV to conduct the analysis and prepare the article. Sue Caleo is an employee of Johnson & Johnson. All remaining authors are employees of Pharmerit BV, which acted as a paid consultant to Johnson & Johnson, who market various antipsychotics.


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Copyright information

© Adis Data Information BV 2008

Authors and Affiliations

  • Bart M. S. Heeg
    • 1
    Email author
  • Joep Damen
    • 1
  • Erik Buskens
    • 1
  • Sue Caleo
    • 2
  • Frank de Charro
    • 1
  • Ben A. van Hout
    • 1
  1. 1.Pharmerit BVRotterdamthe Netherlands
  2. 2.Janssen Pharmaceutica NVBeerseBelgium

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