The multiple sclerosis self-concept change scale: Development and validation of a new measure.

BACKGROUND: Self-concept change may impact psychological wellbeing and functioning in people with MS (pwMS). However, the extent and nature of change in self-concept that pwMS experience is poorly understood, owing to the lack of quantitative measures available to assess this construct. OBJECTIVE: To examine the factor structure, validity, and internal consistency of the newly developed Multiple Sclerosis Self-Concept Change Scale (MSSCCS). METHODS: Items measuring self-concept change were created, reviewed by a panel of experts and pre-tested in a sample of 135 pwMS. A revised list of 51 items were then administered to 1307 pwMS (80.3% female; Age M = 59.21 years, SD = 11.40), together with measures of disease impact and psychosocial functioning. RESULTS: Exploratory factor analysis using principal axis factor extraction in 643 randomly selected participants yielded 23-items measuring 5 latent factors for the final MSSCCS. Confirmatory factor analysis involving the remaining participants supported the 5-factor model, as well as a 2nd order model of "global change". Internal consistency of the total scale was good (α = 0.89). The MSSCCS also demonstrated evidence of concurrent and construct validity. CONCLUSION: The MSSCCS is a reliable and valid assessment, which may assist in enhancing understanding of self-concept change in pwMS.