Quality of life and experiences of psychosis: an examination of research outcomes and a mindfulness-based intervention
Ridler, Joseph Henry
Aims This thesis primarily focuses on examining the role and mechanisms of psychological or psychosocial interventions in improving quality of life (QoL) for people experiencing psychosis. The systematic review aimed to meta-analyse studies that reported both QoL and psychosis symptom outcomes. This allowed comparison of effect sizes between these separate outcomes, to assess statistically significant differences in these outcomes and mediating effects of the type of intervention. The empirical study sought to examine the feasibility of a novel, six-session 1:1 mindfulness-based intervention (MBI) for people experiencing psychosis. This study also aimed to contribute to the growing MBI literature, through examining the feasibility of using multilevel modelling to assess between-session mindfulness practice and metacognitive beliefs as predictors of QoL outcomes of people experiencing psychosis following MBIs. Methods An inclusive systematic review of the literature was conducted to include any study providing pre-post comparison data for psychological or psychosocial interventions for people experiencing psychosis, utilising both QoL and psychosis symptom outcomes. Meta-analyses were conducted on overall outcomes for QoL, and total, positive, and negative psychosis symptoms. Subgroup analyses examined psychological and psychosocial interventions separately, while assessing potential moderation of intervention type (e.g., MBIs). The empirical study assessed feasibility utilising a case series design. Participants were offered six, 60-minute sessions of 1:1 MBI. Multilevel modelling was applied to QoL and general functioning outcomes, with between-session practice and metacognitive beliefs as predictors. All other outcomes were measured pre- and post-intervention. Results Meta-analyses utilising 82 pre-post comparisons across 71 studies indicated statistically significant differences between QoL and total symptom effect sizes. Subgroup analyses suggested that intervention type moderated these effects. Effect sizes were largely maintained following sensitivity and outlier analyses. The feasibility study indicated the study is largely feasible for full trial. However, it is suggested that measures are taken immediately post-intervention and at an extended follow-up, rather than two weeks post-intervention. Reduction of sessions to 30 minutes with one practice was preferred by most participants. Therefore, shorter but more frequent sessions are recommended. Between-session practice adherence was poor for most participants. Metacognitive beliefs improved for all participants from pre- to mid-intervention, however increased post-intervention. All exploratory measures, except general wellbeing, demonstrated trends towards improvement. Discussion This thesis suggests that while psychological and psychosocial interventions improve QoL, they have greater effects on psychosis symptom outcomes. This indicates a need for interventions to be modified in order to address QoL needs more explicitly for people experiencing psychosis. However, issues around QoL assessment are presented. Feasibility and acceptability of the study procedures and intervention were partially confirmed, with some potential adaptations identified. Further research examining metacognitive belief outcomes and factors influencing between-session practice adherence is also recommended.