Adjustment to Multiple Sclerosis : investigating the role of self-concept change

Multiple Sclerosis (MS) is a chronic neurodegenerative disorder that can result in physical, psychological, cognitive, and social difficulties. Due to its wide-ranging impacts, changing self-concept (i.e., the typical ways people think about and describe themselves) is a likely consequence. How MS may influence self-concept in people with MS, however, is not well understood. This may be due in part to limitations in the methodology in prior studies and the lack of a standardised, MS-specific, measure of self-concept change. The aims of this thesis are threefold; firstly, to provide an in-depth account of what is already known in the existing literature about self-concept change following MS diagnosis; secondly, to develop a reliable and valid measure of self-concept change using robust scale development and validation methods; and thirdly, to explore how self-concept change is experienced by people living with MS using both qualitative and quantitative research methodologies. This thesis is comprised of four studies to meet these aims. Firstly, a systematic review of both quantitative and qualitative studies was conducted to determine the current state of the literature concerning self-concept change. Findings from the qualitative synthesis revealed that self?concept change is a common experience for people with MS, and highlighted the varied and complex facets of change. The results of the quantitative synthesis highlighted the sparsity of research in self-concept change, as well as the inconsistencies in self-concept measurement, likely owing to the lack of a standardised scale. The remaining studies addressed this identified methodological limitation by developing and validating a new measure of self?concept change specific for people with MS, and applying the newly created scale in a structural model to examine a plausible process or model of self-concept change. In exploring this likely process of self-concept change, how self-concept change was described by people with MS was first qualitatively examined. This study highlighted a complex experience of self-concept change in people with MS that included a process of change initiated by a major disease-related external event (i.e., diagnosis, symptom escalation, relationship changes, and changes to employment), which appeared to provoke a series of key internal thought processes that facilitated the redefinition of self-concept. The following study used the main findings of the systematic review and qualitative examination of self-concept change to develop and validate a new standardised self-concept change questionnaire: the MS Self-Concept Change Scale (MSSCCS). In this study, a large sample of people with MS (n = 1313) completed the MSSCCS and other validating measures to establish the factor structure, reliability and validity of the new scale. The results of this study demonstrated that the MSSCCS is a reliable and valid measure, which contained two equivalent and interpretable factor structures: (1) a first-order 5-factor model (factors named misplaced self, humanitarian self, compassionate self, social self, and industrious self) and (2) a second-order model whereby the five first-order factors all load onto a single higher-order factor indexing Global Self Change. The fourth and final study applied the new MSSCCS by examining whether a relationship between the degree of MS disability and self-concept change exists and whether Health-Related Quality of Life (HRQoL) and ‘relationship satisfaction’ respectively mediates and moderates this relationship in a moderated mediation structural equation model. While no moderation effect of relationship satisfaction was found, the relationship between MS disability and self-concept change was partially mediated by HRQoL. The primary output from this thesis, the newly developed MSSCCS, is a promising new measure of self-concept change that enables the quantification of the extent of perceived self-concept change in people with MS. An important key finding is that self-concept change is a common experience following MS diagnosis, with various factors including the degree of disability, HRQoL, and changes to personal and professional roles, all contributing to the extent and nature of this change.