OBJECTIVES: To show how Markov matrices can be used to quantify and integrate the risks and benefits of health care interventions when these are measured using health-related quality of life (HRQOL) instruments. To provide an example of this type of evaluation for an HRQOL measure which uses Likert scales for the response options. METHODS: A brief theoretical explanation of the nature and purposes of Markov matrices will be followed by practical examples of their potential in the field of outcomes research using the COOP-WONCA charts in a hypothetical longitudinal study. RESULTS: Markov matrices defining between-state transition probabilities (HRQOL dimension score at each measurement time point) are developed and use of the matrices will be illustrated by providing quantitative definitions and interpretations of the probabilities associated with the principal sub-matrices (main diagonal, upper and lower triangles, upper and lower linear bounds, and simple elements). CONCLUSIONS: The use of theoretical definitions and practical examples will be useful in introducing and discussing the application of Markov matrices as a means of integrating risk and benefit considerations associated with health care interventions measured using HRQOL instruments.