Measurement of health state utilities for economic appraisal A review

Health status measurement for use in economic appraisal of health care programmes is reviewed in this paper, with particular emphasis on utility measurement. A framework for economic appraisal is presented displaying the various components that must be measured, and showing how the three forms of analysis (cost-effectiveness analysis, cost-benefit analysis and cost-utility analysis) relate to the framework and to each other. One of the components in the framework is health status; it can be measured using ad hoc numeric scales, willingness to pay/receive or health state utilities. The determination of health state utilities is reviewed covering the following issues: alternative sources of utilities, health state descriptions, multi-attribute utility approach, determination of appropriate subjects, utility aggregation, and accuracy. Three measurement techniques for health state utilities are described in detail: rating scale, standard gamble, and time trade-off. The use of these methods is described for both chronic and temporary health states and for both health states considered better than death and those considered worse than death.