Background: Self-efficacy is a well-established determinant of emotional distress and quality of life (QOL) in individuals with multiple sclerosis (MS). However, the more fundamental role of illness identity-a novel conceptual model in the context of chronic conditions-has not been examined.
Objective: This study aimed to explore the associations between illness identity, distress, and QOL in individuals with MS, while also assessing the mediating role of MS self-efficacy (MSSE).
Methods: This cross-sectional study used a correlational design and included 160 patients (RRMS = 64, PPMS = 68, SPMS = 28). Data were collected using the WHO QOL Questionnaire (WHOQOL-BREF), the Depression, Anxiety, and Stress Scale (DASS), the MS Self-Efficacy Scale (MSSE), the Illness Identity Questionnaire (IIQ), and illness-related/demographic questions. Data were analyzed using an independent t-test, one-way ANOVA, Pearson correlation, path analysis, and multiple regression.
Results: Engulfment, rejection, acceptance, and enrichment were significantly related to MSSE, while engulfment and MSSE were directly associated with distress. Engulfment, enrichment, MSSE, and distress also had significant direct associations with QOL. MSSE acted as a first-order mediator, and distress as a second-order mediator between illness identity and QOL.
Conclusions: This study highlighted that redefining identity in the context of MS is an important factor relating to self-efficacy, which, in turn, shapes distress and QOL. Psychological interventions targeting illness identity and self-efficacy may help reduce distress and improve QOL.
Keywords: Distress; Illness identity; Multiple sclerosis; Quality of life; Self-efficacy.
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