KMAN Publication Inc. (KMANPUB) Journal of Adolescent and Youth Psychological Studies (JAYPS) 2981-2526 In Press 2027 05 01 Comparison of the Effectiveness of Positive Thinking Training and Mindfulness-Based Cognitive Therapy on Self-Control Skills among Female Secondary School Students in Tehran Province Comparison of the Effectiveness of Positive Thinking Training and Mindfulness-Based Cognitive Therapy on Self-Control Skills among Female Secondary School Students in Tehran Province 1 15 EN Journal Article 2026 09 08 <table> <tbody> <tr> <td> <p><strong>Objective:</strong> The present study aimed to compare the effectiveness of positive thinking training and mindfulness-based cognitive therapy on self-control skills among female secondary school students in Tehran Province.</p> <p><strong>Methods and Materials:</strong> This quasi-experimental study employed a pretest–posttest control group design with two experimental groups. The statistical population consisted of female secondary school students in Tehran Province during the 2025–2026 academic year. Initially, 300 students were screened using the Tangney Self-Control Scale, and 60 students with low self-control scores who met the inclusion criteria were selected and randomly assigned to a positive thinking training group, a mindfulness-based cognitive therapy group, and a control group, with 20 participants in each group. The first experimental group received eight 90-minute sessions of positive thinking training based on Quilliam’s approach, while the second experimental group received eight 90-minute sessions of mindfulness-based cognitive therapy. The control group received no intervention. Data were analyzed using analysis of covariance and Bonferroni-adjusted pairwise comparisons at a significance level of .05.</p> <p><strong>Findings:</strong> After controlling for pretest self-control scores, a significant difference was observed among the three groups in posttest self-control, F(2, 56) = 89.91, p &lt; .001, partial η² = .763. Bonferroni comparisons showed that positive thinking training significantly increased self-control compared with the control group (mean difference = 12.58, p &lt; .001). Mindfulness-based cognitive therapy also significantly improved self-control compared with the control group (mean difference = 16.29, p &lt; .001). Furthermore, mindfulness-based cognitive therapy was significantly more effective than positive thinking training (mean difference = 3.71, p = .006).</p> <p><strong>Conclusion:</strong> Both positive thinking training and mindfulness-based cognitive therapy were effective in improving self-control skills among female secondary school students; however, mindfulness-based cognitive therapy demonstrated greater effectiveness and may therefore be considered a more powerful intervention for strengthening self-regulatory capacities in this population.</p> </td> </tr> </tbody> </table> https://journals.kmanpub.com/index.php/jayps/article/download/6646/12334