Multicomponent positive psychology interventions for promoting adolescents' mental healthan investigation from different methodological approaches

Laburpena

Adolescence is a transitional stage involving many developmental changes, in- cluding biological, physical, and psychological challenges that can affect mental health. From the perspective of the dual-factor model, mental health involves the presence of well-being indicators and the absence of psychological distress indica- tors. According to this model, promotion programs aimed at increasing well-being and reducing psychological distress, namely multicomponent positive psychology interventions (MPPIs), are an effective strategy to endorse adolescents’ mental health. Indeed, the endorsement of adolescents’ mental health has become a pri- mary concern among educational institutions and a fundamental priority for public policies during the last decade. However, the introduction of MPPIs as a tool to promote mental health in the school context has been scarce. Bearing these con- siderations in mind, the objectives of the present thesis are: to review studies that assess the effectiveness of MPPIs in the school setting and to broaden the study of adolescents’ mental health by introducing the phenomenon of time attitudes (Sec- tion 1); and to investigate the impact of an MPPI program on adolescents’ mental health and time attitudes using different methodological approaches (Section 2). To accomplish these objectives, we conducted a systematic review and meta-analysis, a cross-sectional study, and two experimental and longitudinal studies. The general results suggest that MPPIs have a positive effect on subjective well-being in the short term and on psychological well-being and depression symptoms in the short and in the long term. Time attitudes offered new possibilities in the study of ado- lescents’ mental health. Adolescents with a positive time attitude profile reported higher scores for well-being indicators and lower scores for psychological distress indicators (Section 1). The implementation of the MPPI program also helped adoles- cents engage in positive attitudes towards the past, present, and future, which sub- sequently enhanced well-being. More specifically, the intervention program had an impact on transition probabilities from more detrimental profiles to optimal profiles of time attitudes. Similarly, structural changes in the subjective assessment of mental health were observed after the intervention program, highlighting the role of stress during this period (Section 2). A more detailed discussion of the results and future research lines are developed in the thesis.