[Cost-utility analysis; uncertainties restrict applicability]

Assumptions and choices are inherent to cost-utility analysis, the economic technique that provides a generic measure for the quantification of the efficiency of various health-care services. Uncertainty prevails on many of them: on the definition of the output of health care as health gain, on its expression in quality-adjusted life years (QALYs), on the choice of measurement instruments that should provide comparable information across all disease categories, on the choice of the procedure to value health states, on the relative importance of the judgments of patients and the general public, on the quantification of various types of costs, and on the question as to whether, and then how, future health gains should be discounted. The conclusion is that the results of a cost-utility analysis should be interpreted with caution. For the time being, cost-utility analysis cannot be used for direct comparisons of efficiency across all types of health-care services.