Effectiveness of Acceptance and Commitment Therapy in Improving Low Self-Esteem among Adolescents in Selected Junior High Schools in Accra, Ghana

Abstract

Low self-esteem remains a critical psychological concern among adolescents, with far-reaching implications for their academic performance, social relationships, and emotional wellbeing. This study investigated the effectiveness of Acceptance and Commitment Therapy (ACT) in improving self-esteem among adolescents in selected Junior High Schools in Accra, Ghana. The research was guided by Carl Rogers’ Theory of Self-Esteem and Relational Frame Theory, which together provided the conceptual framework for understanding both the development of self-concept and the mechanisms of psychological flexibility targeted by ACT. The objectives of the study were to assess the prevalence of self-esteem, establish the socio-demographic characteristics and socio-cultural associated with low self-esteem as well as effectiveness of ACT in improving low self-esteem among adolescents. The first three objectives were analysed using data at the screening stage (N=416). A quasi-experimental design incorporating baseline, midline, and endline assessments was employed to ascertain the fourth objective (n=124). Purposive sampling techniques were used to select both schools and participants, yielding a total sample of 124 adolescents aged 12–15 years, all transitioning through Junior High School levels (JHS 1–3). Participants were evenly distributed into an intervention group (n=62) and a control group (n=62). Research instruments included a sociodemographic and cultural questionnaire, the Rosenberg Self-Esteem Scale (RSES), and the Acceptance and Action Questionnaire (AAQ-II). The RSES and AAQ-II were administered at all three stages to measure changes in self-esteem levels and psychological flexibility respectively. At baseline, findings revealed that 37.8% of participants presented with low self-esteem, a prevalence consistent with continental evidence of widespread adolescent psychological vulnerability. At midline assessment, 61.1% of adolescents in the ACT group demonstrated improvement, compared to only 22% in the control group. By endline, 75.8% of the ACT group reported significant gains in self-esteem, in contrast to 24.6% in the control group. These differences were statistically significant (p < 0.001) and demonstrated large effect sizes (Cramer’s V = 0.3–0.5). Mediation analysis further explored the role of psychological flexibility in the observed outcomes. While ACT was found to significantly enhance psychological flexibility, Sobel test results indicated a weak mediation effect (z score= 0.72. This suggests that although increased psychological flexibility was a valuable secondary outcome of the intervention, the direct effect of ACT on self-esteem was both strong and statistically reliable (p < 0.001). Overall, the study provides robust evidence that ACT can serve as an effective, contextually sensitive intervention for addressing self-esteem challenges among Ghanaian adolescents. It recommends the integration of ACT into school-based mental health programs, the expansion of psychosocial support services for students, and the implementation of longitudinal and large-scale studies to further validate sustainability and wider applicability across diverse adolescent population.