Effectiveness of Acceptance and Commitment Therapy on Loneliness, Self-Efficacy, and Perceived Social Rejection in Adolescents

Objective: This study aimed to examine the effectiveness of Acceptance and Commitment Therapy (ACT) on loneliness, self-efficacy, and perceived social rejection among adolescents.

Methods and Materials: A quasi-experimental pretest–posttest control-group design was used. Thirty participants were selected through convenience sampling and randomly assigned to an experimental group (n = 15) and a control group (n = 15). The experimental group received eight weekly 90-minute ACT sessions, while the control group received no intervention. Data were collected using the UCLA Loneliness Scale, the General Self-Efficacy Questionnaire, and the Perceived Social Rejection Questionnaire. Data were analyzed using multivariate analysis of covariance and follow-up univariate ANCOVAs in SPSS version 26.

Findings: After controlling for pretest scores, the multivariate effect of group was significant, Wilks’ Lambda = 0.250, F(3, 23) = 23.034, p = .001, η² = .750. Univariate analyses showed significant intervention effects on loneliness, F(1, 27) = 555.477, p < .001, η² = .628; self-efficacy, F(1, 27) = 239.454, p < .001, η² = .528; and perceived social rejection, F(1, 27) = 301.050, p < .001, η² = .614. Compared with the control group, the ACT group showed lower loneliness and perceived social rejection and higher self-efficacy at posttest.

Conclusion: ACT significantly reduced loneliness and perceived social rejection and increased self-efficacy. The findings support ACT as an effective intervention for improving psychological flexibility and social-emotional functioning.