Development and Validation of the Occupational Self-Assessment-Short Form (OSA-SF).

Abstract

The Occupational Self-Assessment, Version 2.2 (OSA 2.2), is a client-centered measure of clients' perceived occupational competence and value. The OSA 2.2 has previously demonstrated good structural validity and internal consistency; however, the administration length could deter therapists from using this assessment in acute care and acute inpatient rehabilitation. To evaluate reliability and validity of the OSA 2.2 in acute care and acute inpatient rehabilitation and to develop and validate the OSA-Short Form (OSA-SF). We performed a descriptive psychometric analysis using the Rasch analytic approach. The data were collected in acute care and acute inpatient rehabilitation. Our convenience sample consisted of 86 patients in acute care and acute inpatient rehabilitation. Participants rated their perceived occupational competence and value by completing the OSA 2.2. We examined psychometric properties of the OSA 2.2 and OSA-SF using a partial credit Rasch model. The 21-item OSA 2.2 was reduced to a 12-item OSA-SF through iterative removal of items on the basis of item-misfit statistics. The OSA-SF demonstrated adequate rating scale functioning, dimensionality, item and person goodness of fit, item targeting, item hierarchies, and item and person separation. Findings indicate that the OSA-SF is a valid and reliable measure that can guide client-centered goal setting and intervention planning for adults receiving acute care and acute inpatient rehabilitation. The OSA 2.2 and the OSA-SF offer a client-centered approach to evaluating patients' self-reported ability and ratings of the importance of performing everyday occupations. These assessments can guide client-centered goal setting in acute care and acute inpatient rehabilitation.