Medical Outcomes Study Short Form 36: a possible source of utilities?

General health-status questionnaires such as the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) are frequently used to measure health-related quality of life. The SF-36, in its current form, cannot be used to measure individuals' utilities or preferences for their health state. Recently, several investigators have explored the possibility of obtaining utilities from the SF-36. This article reviews the SF-36 survey, selected measures of utility, and the differences between health-status and utility measures, with an emphasis on use of SF-36 results to derive utility scores. We searched the literature from January 1966 to July 1999 using MEDLINE and HEALTHSTAR. The terms SF-36, health-status instruments, utilities, and preferences were searched to identify studies that had used both the SF-36 and a utility-based instrument. We first discuss studies that were specifically designed to find a predictive equation to obtain utilities from SF-36 scores. We then discuss studies that examined the correlation between the SF-36 and a utility-based instrument but that were not intended to develop a predictive equation as their primary objective. The studies that have tried to derive utilities from the SF-36 using a predictive equation have used different methodologies; to date, no reliable method has been appropriately validated. The poor correlation reported in most of the studies attests to the complex relationship between utility-based instruments and the SF-36. More work is needed to elucidate if utilities can be obtained from the SF-36.