Validation of the Japanese Society for Surgery of the Hand Version of the Quick Disability of the Arm, Shoulder, and Hand (QuickDASH-JSSH) questionnaire

BACKGROUND The Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) questionnaire is a region-specific, self-administered questionnaire, which consists of a disability/symptom (QuickDASH-DS) scale, and the same two optional modules, the work (DASH-W) and the sport/music (DASH-SM) modules, as the DASH. After the Japanese version of DASH (DASH-JSSH) was cross-culturally adapted and developed, we made the Japanese version of QuickDASH (QuickDASH-JSSH) by extracting 11 out of 30 items of the DASH-JSSH regarding disability/symptoms. The purpose of this study was to test the reliability, validity, and responsiveness of QuickDASH-JSSH. METHODS A series of 72 patients with upper extremity disorders completed the QuickDASH-JSSH, the 36-Item Short-Form Health Survey (SF-36), and the Visual Analog Scale (VAS) for pain. Thirty-eight of the patients were reassessed for test-retest reliability 1 or 2 weeks later. Reliability was investigated by the reproducibility and internal consistency. To analyze the validity, a principal component analysis and the correlation coefficients between the QuickDASH-JSSH and the SF-36 were obtained. The responsiveness was examined by calculating the standardized response mean (SRM; mean change/SD) and effect size (mean change/SD of baseline value) after carpal tunnel release of the 17 patients with carpal tunnel syndrome. RESULTS Cronbach's alpha coefficient in the QuickDASH-DS was 0.88. The intraclass correlation coefficient (ICC) for the same was 0.82. The unidimensionality of the QuickDASH-DS was confirmed. The correlation coefficients between the QuickDASH-DS and the DASH-DS, DASH-W, or the DASH-SM were 0.92, 0.81, or 0.76, respectively. The correlation coefficients between the QuickDASH-DS score and the subscales of the SF-36 ranged from -0.29 to -0.73. The correlation coefficient between the QuickDASH-DS score and the VAS for pain was 0.52. The SRM/effect size of QuickDASH-DS was -0.54/-0.37, which indicated moderate sensitivity. CONCLUSION The Japanese version of QuickDASH has equivalent evaluation capacities to the original QuickDASH.