OBJECTIVES: To evaluate the responsiveness of the SF-36 subscales, the generic physical (PCS) and mental (MCS) components of the SF-36, and the SF-36 Arthritis-Specific Health Index (ASHI) to changes in disability measured by the Health Assessment Questionnaire (HAQ) in RAPOLO. METHODS: We identified 388 participants from RAPOLO, a longitudinal, observational study of RA, who had repeated measures of arthritis specific function (HAQ and ASHI) and general function (SF-36). We categorized patients into three groups according to HAQ score—(1) stable, (2) declined (increase in HAQ score >of 0.25) and (3) improved (a decline in HAQ score of > 0.25). For each group we calculated Guyatt’s statistic--a measure of responsiveness to change. The larger the absolute value of Guyatt’s statistic, the greater the responsiveness to change. RESULTS: Cohort is 79% female; mean disease duration is 13.2 yrs; mean age is 55 yrs. There were 286 participants who had no change in HAQ score. Guyatt’s statistic ranged between 0.04 to 0.17 (Social Functioning). There were 52 participants who declined. The Guyatt’s statistics for the SF-36 ranged from 0.11 (Role Emotional) to 1.88 (Role-Physical). There were 46 participants who improved in HAQ score. The Guyatt’s statistic ranged from 0.14 (Mental Component Summary Score) to 1.58 (Role-Physical). CONCLUSIONS: Statistics less than 0.3 indicate no responsiveness to change, statistics > 0.5 reflect responsiveness to change. The physical subscales of the SF-36, the PCS, and the ASHI were moderately to highly responsive to change in HAQ score. The emotional subscales were not responsive to change in disability.