My best self"efficacy and underlying mechanisms of a positive psychology intervention

Resumen

Positive Psychology Interventions are valuable resources to promote wellbeing in individuals who practice them (Bolier et al., 2013), and, concretely, the Best Possible Self intervention seems to be a promising approach (Loveday et al., 2016). This is a positive intervention that asks individuals to imagine themselves in the best possible future (King, 2001). Although there are many individual published studies about its efficacy, it is still unknown what the overall efficacy of this intervention is, and further research is needed on this issue. In addition, research on the mechanisms which lie beneath the efficacy of this positive activity is scarce. Therefore, the aim of this dissertation is twofold: to explore the overall efficacy of the BPS, and to analyze the role of the mechanisms that can influence its efficacy. Concretely, the role of the temporal focus will be examined. Subsequently, this dissertation has the following specific objectives: 1) To review the overall efficacy of the BPS intervention based on the existing evidence, and to explore the role of the possible moderator variables related to the intervention implementation. 2) To contribute to a more accurate measurement of SWB considering the temporal frame. 3) To design and develop two temporal variants of the original BPS (Best Past Self and Best Present Self), applied through ICTs. 4) To analyze the efficacy of the three temporal versions of BPS, applied through ICTs, to increase wellbeing. 5) To analyze the possible underlying mechanisms that lie beneath their effectiveness, through qualitative analyses of the texts. This dissertation contains five studies (organized in 4 papers) and two additional chapters aimed at addressing the previously mentioned objectives. Chapter 1 described a general introduction of the main topics of this dissertation, including the main characteristics and effects of PPIs and the BPS intervention. In addition, the role of possible factors that can influence the efficacy of these interventions was briefly exposed, as well as the impact that ICTs can have in the field of PPIs. Chapter 2 consists of a systematic review and meta-analysis on the efficacy of the BPS compared with controls, which include the general efficacy levels of the intervention as well as the analyses of possible moderator variables. Chapter 3 is aimed at describing the Spanish validation of a scale that measures life satisfaction along the lifespan. In addition, exploring the temporal aspects of SWB and its relationship with sociodemographic variables and the affective components of SWB. Chapter 4 includes two randomized controlled trials (Study 1 and Study 2) in which the efficacy of the temporal variations of the BPS implemented through ICTs were compared with a control condition. Chapter 5 includes a mixed method design in which a qualitative analysis of the texts included in Study 1 was carried out and combined with quantitative data about the efficacy of the intervention on positive affect. Finally, Chapter 6 presents a general discussion that includes a summary of the main conclusions outlined by the results obtained in the previous publications, as well as the limitations and future directions of this dissertation.