Responsiveness of the Michigan Hand Outcomes Questionnaire--Dutch language version in patients with rheumatoid arthritis.

OBJECTIVE To investigate the responsiveness of the Michigan Hand Outcomes Questionnaire (MHQ) in patients with rheumatoid arthritis (RA) who were treated in a multidisciplinary hand clinic. DESIGN Observational study comparing the responsiveness of the MHQ with that of various other outcome measures for hand function. SETTING Multidisciplinary hand clinic within a tertiary referral center for rheumatologic care. PARTICIPANTS Twenty-eight patients with problems in hand function due to RA were assessed before and 3 months after conservative and/or surgical treatment. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Assessments included, apart from a previously validated Dutch language version of the MHQ, a visual analog scale for pain, grip strength, the Sequential Occupational Dexterity Assessment, the Arthritis Impact Measurement Scales (AIMS) hand and finger function scale, and each patient's rating of subjective change in hand function. Measurements of responsiveness included the standardized response mean (SRM), effect size, and responsiveness ratio. In addition, the Spearman rank correlations (rho) between the change scores of the MHQ and those of other measures of hand function were calculated. RESULTS The mean MHQ total score improved significantly between baseline (mean +/- standard deviation, 48.3+/-12.2) and follow-up (mean, 54.7+/-16.9) (change score, -7.2; 95% confidence interval, -11.1 to -3.3). The SRM, effect size, and responsiveness ratio of the MHQ total score were -0.72, -0.52, and -1.99, respectively. Significant associations were found between the changes of the MHQ total score and each patient's rating of subjective change in hand function (rho=.64, P=.001) and the change score of the AIMS hand function scale (rho=-.24, P=.260). CONCLUSIONS The MHQ proved to be a responsive measure of hand function in patients with RA who were treated in connection with a multidisciplinary hand clinic.