Background: We aimed to evaluate the validity and reliability of the Persian version of the WOrk-Related Questionnaire for UPper extremity disorders (WORQ-UP) questionnaire in a working population with upper extremity musculoskeletal disorders. Methods: We enrolled 181 patients with upper extremity conditions to complete the Persian WORQ-UP. A total of 35 patients returned after 1 week to complete the questionnaire again. To test the construct validity, patients responded to the Persian Quick Disabilities of the Arm, Shoulder and Hand questionnaire (Quick-DASH) at the first visit. The correlation between Quick-DASH and the WORQ-UP was assessed using Spearman correlation coefficient. Internal consistency (IC) was tested using Cronbach's alpha, and test-retest reliability was measured using the intraclass correlation coefficient (ICC). Results: Spearman correlation coefficient was 0.630 (p < 0.001), indicating a strong correlation between Quick-DASH and WORQ-UP. Cronbach's alpha was 0.970, which is considered excellent. ICC for the total score of the Persian WORQ-UP was 0.852 (0.691-0.927), indicating good to excellent reliability. Conclusions: Our study demonstrated that the Persian version of the WORQ-UP questionnaire has excellent reliability and IC. Construct validity showed a moderate to strong correlation between WORQ-UP and Quick-DASH, which provides a platform for the workers' population to assess the extent of disability and follow the progress along the treatment course. Level of Evidence: Level IV (Diagnostic).
Keywords: Persian; Psychometric properties; Questionnaire; Reliability; Validity; WORQ-UP.