A short activity-related scale for measuring shoulder function in patients with subacromial pain: the DASH 7

Subacromial pain is a common cause of shoulder dysfunction that negatively affects quality of life. Currently, most outcome measures for shoulder pain are applied to a heterogeneous group of patients. Of these measures, the Disabilities of the Arm, Shoulder, and Hand (DASH) is the most widely recognized test with which to assess patients with subacromial pain. The primary aim of this study was to assess the content validity of DASH for patients with subacromial pain, with a secondary aim to test responsiveness to a modified set of DASH items tailored to these patients. There were 129 patients who reported activities in the Patient-Specific Functional Scale (PSFS). To assess validity, 5 independent physiotherapists matched PSFS activities to the most appropriate DASH item. DASH items identified as being of greatest importance to patients were those corresponding to the highest number of PSFS-matched activities. Calculations were made for responsiveness and internal consistency. Physiotherapists matched DASH items to 271 PSFS activities, reaching agreement for almost 80%. Seven DASH items (DASH 7) were identified as being particularly important. Effect size data (Cohen's d) were 0.93 for DASH 7, 0.92 for DASH 30, and 0.85 for QuickDASH; the corresponding Cronbach's α values (for DASH 7, DASH 30, and QuickDASH) were 0.84, 0.94, and 0.86, respectively. DASH 7 is a short, patient-centered, and activity-related scale that can measure shoulder function in patients with subacromial pain using a quarter of the original DASH items. DASH 7 demonstrated responsiveness, with a satisfactory level of internal consistency.