Rheumatoid arthritis (RA) is chronic, painful, disabling condition resulting in significant impairments in physical, emotional, and social health. We used different methods and perspectives to evaluate the responsiveness of PROMIS® short forms (SFs) and identify minimal and meaningful score changes.
Adults with RA enrolled in a multi-site prospective observational cohort completed PROMIS Physical Function, Pain Interference, Fatigue, Participation in Social Roles/Activities SFs, PROMIS-29, and pain, patient global, and rated change in specific symptoms and RA (a little vs. lot better or worse) at the second visit. Physicians recorded joint counts, MD Global Assessment, and change in RA at visit 2. We compared mean score differences for minimal and meaningful improvement/worsening using patient and MD change ratings and distribution-based methods, and visually inspected empirical cumulative distribution function curves by change categories.
The 348 adults were mostly (81%) female with longstanding RA. Using patient ratings, generally 1-3 point differences were observed for minimal change and 3-7 points for meaningful change. Larger differences were observed with patient vs. physician ratings and for symptom-specific vs. RA change. Mean differences were similar among SF versions. Prespecified hypotheses about change in PROMIS Physical Function, Pain Interference, Fatigue and Participation and legacy scales were supported.
PROMIS SFs and the PROMIS-29 Profile are responsive to change and generally distinguish between minimal and meaningful improvement and worsening in key RA domains. These data add to a growing body of evidence demonstrating robust psychometric properties of PROMIS and supporting use in RA care, research, and decision-making.