Reliability and validity of the upper limb DASH questionnaire in patients with distal radius fractures

Aim: The purpose of the study was to verify test criteria of the upper-limb DASH questionnaire in patients with Colles' fractures. Methods: 107 of 139 patients with Colles' fractures treated operatively were examined and asked to complete the questionnaire. To establish reliability, the item answers of all questionnaires were analysed by using Cronbach's Alpha correlation coefficient and corrected item total correlation. Construct validity was evaluated by comparing the DASH points with clinical measures according to Gartland/Werley and Castaing (Spearman correlation coefficient). Discriminant validity was assessed by comparing the DASH points of patients with AO-type A/B fractures and AO-type C fractures (Mann-Whitney U-Test). Results: 2.7 percent of all questionnaires were unusuable. The time to fill out the questionnaire was on average 12 minutes. Cronbach's alpha values were high in all scales (alpha > 0.8). No items were found unsuitable (corrected item total correlation > 0.5 in 28 of 30 questions). DASH scores were correlated with ROM deficits and clinical measures of wrist function (r = 0.53; r = 0.59; r = 0.52, p < 0.01). The questionnaire could discriminate patients with different fracture types (p < 0.05). Conclusions: DASH is a workable, reliable and valid instrument for patients with Colles' fractures.