Reliability and validation properties of the Malaysian language version of the Occupational Self Assessment version 2.2 for injured workers with musculoskeletal disorders

Introduction: It has been difficult for occupational therapists in Asia to use occupational therapy assessments, such as the Occupational Self Assessment (OSA) version 2.2, that are not validated in the local language. This study aimed to produce and assess the psychometric properties of a Malaysian version of the 21-item OSA. Method: The translation process involved the forward and back translation from the original English version into the Malaysian version, followed by field tests conducted with a small group of occupational therapists and workers to confirm the translation's equivalence and appropriateness. A total of 35 Malaysian injured workers with musculoskeletal disorders who were not involved in a return to work programme were assessed using the Malaysian version of the OSA. Twenty-three were reassessed 7-14 days later to determine test-retest reliability. Results: The Malaysian version of the OSA showed acceptable reliability (internal consistency, corrected item correlation and test-retest reliability) and validity (convergent and discriminant validity). Conclusion: The results suggest that the OSA is reliable and valid in assessing occupational functioning for injured Asian workers with musculoskeletal disorders.