Cross-cultural adaptation, reliability, and validity of the Work Role Functioning Questionnaire to Brazilian Portuguese

Introduction The study objectives were to translate and adapt the Work Role Functioning Questionnaire (WRFQ) into the Brazilian Portuguese language and evaluate its reliability in patients experiencing musculoskeletal disorders. Methods The cross-cultural adaptation was performed according to the internationally recommended methodology, using the following guidelines: translation, back-translation, revision by a committee, and pretest. At first, the questionnaire was independently translated by two bilingual translators, who had Portuguese as their mother language. Subsequently, two other translators whose mother language was English did the back-translation. A committee composed of five specialists revised and compared the translations obtained, developing the final version for pretest application. The pretest was carried out with 30 patients experiencing musculoskeletal disorders. Psychometric properties were evaluated by administering the questionnaire to 105 subjects with musculoskeletal disorders and receiving physical therapy treatment. The reliability was estimated through stability and homogeneity assessment. The construct validity was tested comparing subjects experiencing musculoskeletal disorders to healthy workers. Results The results indicated good content validity and internal consistency (Cronbach alpha = 0.95). Cronbach alpha for each scale was > 0.85, except for the social demand scale. The Intraclass Correlation Coefficient for the test-retest reliability was satisfactory for mental demands (ICC = 0.68) and excellent for the others (0.82-0.91). In relation to the construct validity, the mean score obtained for each scale was lower for physical, work scheduling, and output demands in the subjects with musculoskeletal disorders. There was a significant difference (p < 0.001) between the groups in comparison to work scheduling, physical, and output demands. Conclusions The data showed that the cross-cultural adaptation process was successful and the adapted instrument demonstrated psychometric properties making it reliable to use in Brazilian culture.