Abstract
PURPOSE: This study aimed to evaluate the validity, reliability, and feasibility of the Persian version of the Relative Mastery Scale as a measure of the Occupational Adaptation Model in caregivers of people with multiple sclerosis. METHOD: In a cross-sectional study, after translation, face and content validity, the caregivers completed the Relative Mastery Scale and the Canadian Occupational Performance Measure. Expanded Disability Status Scale for people with multiple sclerosis was reported by neurologist. Also, convergent validity, internal consistency, test-retest reliability, and exploratory factor analyses were evaluated. RESULTS: A total of 150 caregivers completed both instruments. Cronbach's α = 0.852 and ICC = 0.838 were good. The convergent validity of the total Relative Mastery Scale score was confirmed with a significant correlation with Canadian Occupational Performance Measure (r > 0.67, p < 0.001) and Expanded Disability Status Scale score (r > 0.34, p < 0.001). The Persian-Relative Mastery Scale was found as a multidimensional instrument with three items that appeared to be redundant. CONCLUSION: The Persian-Relative Mastery Scale had acceptable reliability and validity for evaluating mastery in Persian-speaker caregivers.