Introduction Musculoskeletal disorders (MSD) are nowadays seen within a biopsychosocial framework, including salutogenic factors, motivation factors, and coping ability. Such a framework recognizes the importance of motivational factors in health promotion and in rehabilitation. The Motivation for Change Questionnaire (MCQ) has been developed to measure the strength of individuals’ motivation for change in life, MCQ part 1, and work situation, MCQ part 2. The purpose of the study was to test the content and concurrent validity of the MCQ on patients with prolonged musculoskeletal disorders referred to interdisciplinary rehabilitation as a basis for use in medical and occupational rehabilitation. Methods Content validity was studied among an expert group of 20 rehabilitation professionals at a rehabilitation centre, and with 10 individuals suffering from prolonged MSD in the south of Sweden. The experts evaluated the clinical relevance of each question in MCQ. Concurrent validity was studied on 58 patients with prolonged MSD at an interdisciplinary rehabilitation centre in the south of Sweden. They answered MCQ, QPS Nordic questionnaire, KASAM and the Action theory questionnaire. Spearman’s rank correlation coefficient was used in the analyses. Results The MCQ covered and measured areas of relevance according to content validity. No floor effects in any of the subscales of MCQ part 1 were seen. In MCQ part 2, floor effects were seen in two sub indexes. As for concurrent validity subscales of MCQ correlated significantly with QPS Nordic questionnaire and KASAM. Conclusions Findings so far indicate the instrument to be valid for use within the present patient group. The questionnaire can be used to identify patient’s motivating factors for change in life and work, as a basis for motivational work within rehabilitation.