Using discrete choice experiments to value preferences for pharmacy services

Objective: This paper describes the application of discrete choice experiments (DCEs), in the measurement of consumers' preferences for pharmacy services. Summary: Patients' preferences for healthcare influence strongly their use of services. Quantifying revealed preferences for services (what services people use) is not always possible because either the service does not yet exist or the consumer has no experience of it. There is a need for tools that measure stated preference (what people say they will do) for healthcare, to allow development of new services. DCEs have been used in the valuation of preferences for healthcare services and interventions and can be applied usefully to the valuation of preferences for pharmacy services. DCEs assume that preferences are based on preferences for different attributes of a service, and that consumers are prepared to trade off one attribute against another, such as effectiveness versus side-effects. In a DCE study, respondents make hypothetical choices between scenarios of services with fixed attributes, but varying levels, revealing their strength of preference for attributes of that service. These data are analysed using regression, which generates coefficients that quantify the direction and magnitude of preferences. Marginal rates of substitution and willingness to pay for each attribute can be estimated, which provide powerful information for future service provision. For this approach to be applied in practice, key methodological issues must be handled explicitly, principally scenario design, attribute and level selection, orthogonality, level balance, minimal overlap and utility balance. A hypothetical example of a DCE designed for valuing consumers' preferences for a medication review service for the elderly is described. © 2005 The Authors.