Translation, cross-cultural adaptation, and validation of the Persian version of the multiple sclerosis self-concept change scale

Multiple sclerosis (MS) is a chronic demyelinating disorder of the central nervous system that affects millions worldwide and imposes profound physical and psychological challenges. Among these, changes in self-concept play a key role in emotional well-being, adaptation to the disease, and overall quality of life in people with MS (pwMS). Despite its clinical importance, there is no validated Persian instrument to assess self-concept change in this population. This study aimed to translate and culturally adapt the Multiple Sclerosis Self-Concept Change Scale (MSSCCS) into Persian and evaluate its psychometric properties. The translation and cross-cultural adaptation of the MSSCCS into Persian adhered to a standardized methodology. Content validity was evaluated using the Content Validity Index (CVI) and Content Validity Ratio (CVR). Construct validity was examined through Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Convergent and discriminant validity were assessed by calculating the Average Variance Extracted (AVE) and Construct Reliability (CR), respectively. The internal consistency and test-retest reliability of the Persian MSSCCS were determined using Cronbach’s alpha and the Intraclass Correlation Coefficient (ICC). A total of 370 participants were included (mean age = 31.32 ± 6.55 years; 63.5% female; 62.4% married). Exploratory factor analysis of the Persian MSSCCS revealed a five-factor structure, explaining 67.79% of the total variance. Item loadings ranged from 0.654 to 0.866 across the factors. Internal consistency was high, with Cronbach’s α = 0.845 for the total scale and 0.762–0.917 for subscales. Test–retest reliability was excellent (ICC = 0.972; factor-level ICCs = 0.901–0.968). Convergent and discriminant validity were supported (CR = 0.814–0.917; AVE = 0.556–0.674; McDonald’s Omega = 0.92). The Persian MSSCCS showed a stable five-factor structure with strong reliability and validity, supporting its use as a culturally adapted tool for assessing self-concept change in Persian-speaking individuals with multiple sclerosis.