To test the validity of the Modified Stanford Health Assessment Questionnaire (MHAQ) for assessment of physical disability in rheumatoid arthritis (RA).
Sixty-one RA patients with mean age of 61 years and median disease duration of four years were included in this cross sectional study. The patients completed the MHAQ. Four simple function tests were performed (walk test, chair test, upper extremity mobility test, and grip strength) and a modified Larsen score was established. Pain score (VAS) and laboratory variables for inflammation were recorded.
MHAQ, function tests, pain, and C reactive protein (CRP) showed highly significant mutual correlations (p < 0.01). However, MHAQ did not correlate with Larsen score (R = 0.06; NS), while most function tests did (walk test, R = 0.29; p < 0.05; chair test, R = 0.21; NS; mobility test, R = 0.36; p < 0.01 and grip strength, R = -0.35 p < 0.01). The superiority of function tests was even more pronounced after four years (walk test, R = 0.31; p < 0.05; chair test, R = 0.50; p < 0.01; mobility test, R = 0.49; p < 0.01; grip strength, R = -0.52; p < 0.01; MHAQ, R = 0.34; NS).
Objective function tests are preferable to MHAQ in the assessment of physical disability in RA.