Responsiveness of self-report and therapist-rated upper extremity structural impairment and functional outcome measures in early rheumatoid arthritis.

Objective To provide a responsiveness analysis of the self-report and therapist-rated upper extremity functional outcome measures used in a rehabilitation trial. Methods A variety of commonly used therapist-assessed and self-report structural impairment and functional outcome measures were compared for the ability to detect and measure change in wrist and hand status in an early rheumatoid arthritis population over 12 months. Responsiveness was measured using the standardized response mean (SRM) and effect size (ES). Results The most responsive measures were the Michigan Hand Outcomes Questionnaire (SRM 0.49 [95% confidence interval (95% CI) 0.27, 0.72], ES = 0.37 [95% CI 0.21, 0.54]), dominant metacarpophalangeal joint ulnar deviation (SRM 0.46 [95% CI 0.27, 0.65], ES = 0.58 [95% CI 0.34, 0.82]), and mean power handgrip test (SRM 0.45 [95% CI 0.26, 0.64], ES = 0.32 [95% CI 0.18, 0.45]) The least responsive measure was the Health Assessment Questionnaire (SRM −0.12 [95% CI −0.31, 0.08], ES = −0.08 [95% CI −0.21, 0.05]). Conclusion Over 12 months, there was substantial variation in wrist and hand outcome measures to detect change over time in an early RA population. Careful consideration is required to choose the most appropriate measure that can detect change.