Validity assessment of the disabilities of arm, shoulder, and hand questionnaire (DASH) for patients with psoriatic arthritis

Objective. To determine whether patients' perception of their functional ab ility, as measured by the disabilities of arm. shoulder, and hand (DASH) qu estionnaire, correlates with clinical measures of articular status in patie nts with psoriatic arthritis (PsA). Methods. patients attending the University of Toronto Psoriatic Arthritis C linic between June and August 1997 were asked to complete a DASH questionna ire during their visits. Clinical assessments were performed according to a standard protocol including number of actively inflamed joints, total numb er of damaged joints, and grip strength. Spearman rank correlations were us ed to examine the relationship between clinical measures and the DASH quest ionnaire. Results. Fifty consecutive patients. 28 men and 22 women, (mean age 49.2 yr s, mean disease duration 13 yrs) were included. DASH scores correlated with clinical measures of upper extremity function including right grip strengt h (r = -0.47, CI -0.67, -0.21) and number of active joints in the upper lim bs (r = 0.65, CI 0.46, 0.79). As expected, the correlation between DASH sco res and total number of active joints (r = 0.40, CI 0.14, 0.61) was lower t han that between DASH scores and number of active joints in the upper limbs . The DASH was unrelated to clinical damage. Conclusion. DASH is a valid instrument for assessing upper extremity functi on and inflammatory disease activity in patients with PsA.