Job-related self-efficacy in musculoskeletal disorders - a questionnaire.

Background: The Return-To-Work Self-Efficacy Scale questionnaire maps self-efficacy upon return to work following acute lower back pain. We wished to translate and validate the questionnaire, as well as to assess the concordance between the translated form and two other forms.
Material and Method: The questionnaire was translated into Norwegian according to recommended guidelines. Employees in the health and care service with musculoskeletal symptoms were recruited for the study. Cross-cultural validity was assessed by principal component analysis and internal consistency by Cronbach's alpha. Conceptual validity was assessed by correlation between the translated form and simultaneous measurements from two questionnaires that focus on closely related characteristics: the Tampa scale for kinesiophobia and the Demand-ControlSupport model.
Results: The Norwegian questionnaire is called 'Job-related self-efficacy'. Of a sample of 229 persons, 206 (89.9 %) were included in the analyses. Principal component analysis supported cross-cultural validity through findings of a three-factor structure in accordance with the original questionnaire. Internal consistency was high for all questions in the questionnaire (0.95), as well as for each of the three factors: meet job requirements (0.99), communicate needs to others (0.97) and adapt work duties (0.96), after adjusting for the number of questions. There were low correlations (< 0.40) between Job-Related Self-Efficacy and the Tampa scale for kinesiophobia, and the various factors in the Demand-Control-Support questionnaire, respectively.
Interpretation: The 'Job-Related Self-Efficacy' questionnaire has satisfactory cross-cultural validity after it was translated, and satisfactory internal consistency.