304 • MEDICAL DECISION MAKING/JUL–AUG 2006 EDITORIALS The Transient Nature of Utilities and Health Preferences

There are 2 well-known findings in the utilityassessment literature: First, patients tend to assign higher utilities to their health state than the general public does. This is a consistent finding that begs the question whose utilities to use in cost-effectiveness analyses that inform decisions for resource allocation.1 Second, utilities are unstable. The same people can produce different utilities about the same health states at different times in their lives. Even though the evi-dence for this is not equivocal,2,3 the question about the “best ” time to elicit utilities remains. In addition to methodological issues about how well health states are described to respondents, the between- and within-subject variation in utilities has been attributed to a number of psychological phe-nomena, some of them related or overlapping (se