Iranian Association for Intelligence and Talent Studies International Journal of Education and Cognitive Sciences 3041-8828 In Press 2027 05 01 Comparison of the Effectiveness of Schema Therapy and Behavioral Activation on Depression Severity and Sleep Quality among University Students with Major Depressive Disorder Comparison of the Effectiveness of Schema Therapy and Behavioral Activation on Depression Severity and Sleep Quality among University Students with Major Depressive Disorder 1 15 EN Journal Article 2026 05 10 <p><strong>Purpose: </strong>This study compared the effectiveness of schema therapy and behavioral activation in reducing depression severity and improving sleep quality among university students with major depressive disorder.</p> <p><strong>Methods and Materials: </strong>A quasi-experimental pretest-posttest design with a control group and two-month follow-up was used. Forty-five students were purposively selected and randomly assigned to schema therapy, behavioral activation, and control groups. Following attrition, 40 participants completed depression assessments and 39 completed sleep-quality assessments. The intervention groups received group treatments, whereas the control group received no intervention. Depression severity was measured using the Beck Depression Inventory-II, and sleep quality was assessed using the Pittsburgh Sleep Quality Index. Data were analyzed using mixed analysis of variance and Bonferroni comparisons.</p> <p><strong>Findings:</strong> Significant time, group, and group-by-time effects were found for depression severity. The interaction effect was significant, F(2.473, 45.769) = 49.408, p &lt; .001, partial eta squared = .728. Significant effects were observed for sleep quality, including a group-by-time interaction, F(2.261, 40.716) = 7.461, p = .001, partial eta squared = .293. Both interventions significantly reduced depression severity and poor sleep-quality scores from pretest to posttest, and improvements remained stable at follow-up. Treatment groups performed better than the control group. No significant differences were found between schema therapy and behavioral activation at posttest or follow-up.</p> <p><strong>Conclusion:</strong> Schema therapy and behavioral activation were comparably effective in reducing depression severity and improving sleep quality among students with major depressive disorder. Both approaches may be applied in counseling settings, with treatment selection guided by characteristics and maintaining mechanisms.</p> https://www.journalecs.com/index.php/ecs/article/download/429/370