Comparison of the Effectiveness of Schema Therapy and Dialectical Behavior Therapy on Interpersonal Relationships in Patients with Borderline Personality Disorder

Abstract

ABSTRACT The present study aimed to compare the effectiveness of schema therapy and dialectical behavior therapy on interpersonal relationships in patients with borderline personality disorder. From a methodological perspective, this research employed a quasi-experimental design with a pretest–posttest control group. The statistical population included all individuals who, with a diagnosis or symptoms of borderline personality disorder, had referred to psychiatric centers, psychological service providers, and clinics in the city of Tehran during the years 2024 to 2025. The study sample consisted of 45 patients selected through purposive nonrandom sampling and subsequently randomly assigned to three groups of 15 participants each (two experimental groups and one control group). The first experimental group received group schema therapy in 16 sessions of 60 minutes each, while the second experimental group underwent group dialectical behavior therapy in 16 sessions of 60 minutes each. The control group did not receive any therapeutic intervention during the course of the study. Data collection instruments included the Structured Clinical Interview for Personality Disorders, the Borderline Personality Questionnaire, and the Interpersonal Relationships Questionnaire developed by Mahmoudi et al. (2016). The collected data were analyzed using repeated-measures analysis of variance. The results indicated a significant difference between the effectiveness of the two therapeutic approaches across the components of interpersonal relationships. Accordingly, it can be concluded that schema therapy, compared to dialectical behavior therapy, demonstrates greater effectiveness in improving interpersonal relationships in patients with borderline personality disorder and can be considered an efficient intervention for enhancing interpersonal functioning in this population.