ARE HEALTH-RELATED QUALITY-OF-LIFE MEASURES AFFECTED BY THE MODE OF ADMINISTRATION

While measures of health related quality of life (HRQOL) are increasin gly being used as outcomes in clinical trials, it is unknown whether H RQOL assessments are influenced by the method of administration. We co mpared telephone, face to face, and self administration of a commonly- used HRQOL measure, the SF-36. Veterans (N = 172) receiving care in th e General Medicine Clinic were randomized into groups differing only i n order of administration. All patients were asked to complete the SF- 36 three times over a 4-week period. The SF-36 demonstrated high inter nal consistency, regardless of mode of administration, but showed larg e variation over short intervals. This variation may: (1) increase dra matically sample size requirements to detect between-group differences in randomized trials and (2) reduce the SF-36's usefulness for clinic ians wishing to follow individual patients over time.