Quality-of-life measures as providers of information on value-for-money of health interventions. Comparison and recommendations for practice.

Three different approaches to measuring quality of life have been developed. Global scales (e.g. time trade-off, visual analogue), multi-attribute utility scales and multidimensional scales (which may be generic or disease-specific). Each of these approaches to measurement provides different kinds of information about quality of life and each can be used to provide information to healthcare purchasers concerning the relative value-for-money of health interventions. The value-for-money of health interventions, in terms of quality of life, can be demonstrated in 2 ways: a formula-driven approach based on cost-utility analysis, which uses scales generating the unit of a quality-adjusted life-year (i.e. global and multi-attribute utility); and a non-formula-driven approach, which uses scales generating multidimensional profiles of quality of life (i.e. multi-attribute utility and multidimensional). Analysis shows that no single approach is sufficient, and that healthcare purchasers should use a variety of types of information in their decision-making, including both cost-utility and informal approaches. Healthcare resource allocation is inevitably a value-dependent activity.