ARTHRITIS SPECIFIC GLOBAL HEALTH ANALOG SCALES ASSESS GENERIC HEALTH-RELATED QUALITY-OF-LIFE IN PATIENTS WITH RHEUMATOID-ARTHRITIS

Objective. Quality-of-life assessment is receiving increased attention as an outcome measure in rheumatoid arthritis (RA). The most widely u sed instruments use Variations on a vertical Visual analog scale (VAS) . Since the Health Assessment Questionnaire (HAQ), Arthritis Impact Me asurement Scales (AIMS), and other instruments have long included a '' global'' arthritis horizontal VAS (GLOB), we studied whether these 2 a pproaches assess the same concept. Methods. We studied 663 patients wi th RA from 4 ARAMIS (Arthritis, Rheumatism, and Aging Medical Informat ion System) centers and had them complete, in different parts of the s ame HAQ, the GLOB and the Torrance ''feeling thermometer'' (FT). Resul ts. The 2 scales were highly correlated (r = -0.676; p < 0.001). Relia bility (estimated by 6 month test-retest) was 0.62 for the FT and 0.83 for the GLOB. The GLOB correlated more strongly than the FT with disa bility (r = 0.561 vs -0.507) and pain (0.630 vs -0.553). In stepwise r egressions, pain and then disability were the dominant predictors of b oth GLOB and FT, followed weakly by joint count and then other variabl es. Patients with greater disability placed more emphasis on pain and patients with greater pain appeared to value more the contribution of disability. Change scores over 6 months between GLOB and FT correlated very well (-0.59). Conclusion. ''Health'' and ''health related qualit y-of-life'' are nearly equivalent terms. Since large longitudinal rheu matology databases contain thousands of global health VAS values, data for longitudinal quality-of-life studies in arthritis are already ava ilable, and this dimension may readily be added to longterm outcome as sessment. In patients with RA, ''generic'' and ''disease specific'' as sessments yield very similar results.