Translation and psychometric validation of the traditional Chinese version of the Western Ontario Rotator Cuff (WORC) Index.

Translate the Western Ontario Rotator Cuff (WORC) Index into Traditional Chinese (WORC-TC), validate its psychometric properties, and adapt it to rotator cuff tears (RCTs) in patients who only understand Traditional Chinese. Translation and psychometric validation were performed. A total of 210 patients completed the WORC-TC, Quick Disability of the Arm, Shoulder, and Hand (QuickDASH), 12-item Short-Form Health Survey (SF-12), Numerical Pain Rating Scale (NPRS), and State Anger Scale (SAS) questionnaires. Construct validity and internal consistency were evaluated. Test-retest reliability analyses were conducted on a 30-patient sub-sample. The translation and linguistic validation process modified one item. Exploratory factor analysis identified a four-factor structure explaining 66.132% variance. The WORC-TC demonstrated convergent validity with QuickDASH (r = 0.834, p < 0.001), NPRS (r = 0.754, p < 0.001), and SF-12 (r = -0.702, p < 0.001), and divergent validity with the SAS (r = 0.286, p < 0.001). Known-group validity was confirmed, with significant differences between high- and low-pain groups (p < 0.001). The WORC-TC showed satisfactory internal consistency (Cronbach's alpha: 0.94) and good test-retest reliability (intraclass correlation coefficient: 0.79). The WORC-TC can reliably evaluate quality of life in patients with RCTs who exclusively use Traditional Chinese.