Modified Chinese disabilities of arm, shoulder and hand tool : validity and reliability for upper extremity injuries

Abstract

Design: Clinimetric evaluation study. Introduction: The Chinese Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire has necessitated the development of a revised version to the specific needs of individuals with upper extremity injuries with the progress of times and lifestyle changes. Purpose of the study: This research aimed to evaluate the reliability and validity of Modified Chinese Disability of Arm, Shoulder and Hand (MC-DASH) questionnaire in individuals with upper extremity injuries. Methods: One hundred and one individuals with upper extremity injuries (UEI) were recruited. The function of upper extremity was measured using the electronic version of MC-DASH, and compared against the Chinese Disability of Arm, Shoulder and Hand. The MC-DASH was reassessed within three days in all individuals. We investigated the internal consistency, test-retest reliability, content validity, criterion validity, and construct validity of MC-DASH. Results: The internal consistency was deemed sufficient, as indicated by a Cronbach's alpha of 0.986 and an intraclass correlation coefficient of 0.957. Moreover, the mean total scores of MC-DASH on the first-test and retest were 37.86 and 38.19, respectively (ICC: 0.957, 95 %CI: 0.937–0.971, p < 0.001). Furthermore, the MC-DASH version exhibited satisfactory content validity evidenced by its strong correlation (R= 0.903, p < 0.001) with the Chinese DASH. Three major influencing factors were identified from 37 items. The cumulative variance contribution rate of the MC-DASH questionnaire was 75.76 %, confirming its construct validity. Conclusion: The Modified Chinese Disability of Arm, Shoulder and Hand questionnaire has been shown to be a valid, reliable, and practical tool for use in patients with upper extremity injuries.