Reliability, validity and responsiveness of the Arabic version of the Disability of Arm, Shoulder and Hand (DASH-Arabic)

Purpose: To investigate the psychometric properties (reliability, validity and responsiveness) of the DASH-Arabic in a cohort of Arabic patients presenting with various upper extremity conditions. Methods: Participants were 139 patients with various upper extremity conditions, who completed the DASH-Arabic at the baseline, 2-5 days later and 30-36 days later. Participants completed demographic data forms, the SF-36 and VAS at baseline, and a Global Rating of Change scale at first and second follow-ups. Results: Cronbach's alpha of the DASH-Arabic was 0.94. Test-retest reliability was excellent with an ICC of 0.97. The SEM was 3.50 and the MDC95 was 9.28. Construct validity of the DASH-Arabic with the SF-36 subscales and VAS scores ranged from r-0.32 to -0.57, all statistically significant (p < 0.001). The effect size (ES) for the DASH-Arabic was 1.39 and its standard response mean was 1.51. The area under the curve was 0.82 (95% Cl = 0.72-0.92, p < 0.001). The optimally efficient cutoff for an improvement was found to be a difference of 15 DASH points. Conclusions: The DASH-Arabic is a reliable, valid and responsive upper extremity outcome measure for patients whose primary language is Arabic; it can be used to document patient status and outcomes and support evidence-based practice.