A mixed-methods investigation of the Best Possible Selves intervention: Relationships and thriving

Positive psychology has been criticised as being dominated by quantitative research. As a field, positive psychology has also tended to be overly focused on individual well-being, on the 'self' rather than the 'other'. The research described in this thesis addressed both these issues by: (a) conducting a mixed-methods research program which consisted of an experiment (n = 141) using a participant-focused, qualitative lens in conjunction with quantitative analysis, and (b) considering the role of both the other, and the self, in data analysis, and the development of an other-focused intervention. Results are presented as five research papers, two of which have been published, the other three are under review. The Best Possible Self (BPS) was the intervention used in this research program. The BPS is an expressive-writing activity in which participants write about their life working out in the best possible way. The first paper (published) of this program of study was a critical review of the BPS literature, which categorised the extant research by type of evidence sought, and synthesised the results from the 31 studies to determine the efficacy of the BPS intervention. The literature review concluded with the identification of topics for future research. Gaps in the literature which were addressed and presented in the remaining four papers included: the potential of the BPS as a hope intervention; the broaden-and-build theory of positive emotions as a potential mechanism explaining efficacy; the lack of qualitative analysis of BPS texts; and the overly individualistic focus inherent in the BPS activity.