Preference-based approaches to measuring the benefits of perinatal care.

Studies that measure benefits of health care interventions in natural or physical units cannot incorporate the several health changes that might occur within a single measure, and they overlook individuals' preferences for those health changes. This paper discusses and critically appraises the application of preference-based approaches to the measurement of the benefits of perinatal care that have developed out of economic theory. These include quality adjusted life year (QALY)-based approaches, monetary-based approaches, and discrete choice experiments. QALY-based approaches use scaling techniques, such as the rating scale, standard gamble approach, and time trade-off approach, or multi-attribute utility measures, to measure the health-related quality of life weights of health states. Monetary-based approaches include the revealed preference approach, which involves observing decisions that individuals actually make concerning health risks, and the willingness-to-pay approach, which provides a framework for investigating individuals' willingness to pay for benefits of health care interventions. Discrete choice experiments describe health care interventions in terms of their attributes, and elicit preferences for scenarios that combine different levels of those attributes. Empirical examples are used to illustrate each preference-based approach to benefit measurement, and several methodological issues raised by the application of these approaches to the perinatal context are discussed. Particular attention is given to identifying the relevant attributes to incorporate into the measurement instrument, appropriate respondents for the measurement exercise, potential sources of bias in description and valuation processes, and the practicality, reliability, and validity of alternative measurement approaches. The paper's conclusion is that researchers should be explicit and rigorous in their application of preference-based approaches to benefit measurement in the context of perinatal care.