The Effectiveness of Unified Transdiagnostic Therapy on Self-Concept and Psychological Disorder of the Students with Depression Symptoms

Background and Purpose: Depression as a psychological disorder can negatively affect one's important functions in various dimensions. As a result, not paying attention to the psychological and emotional problems of people with depression can aggravate their problems and in some cases suicidal thoughts. Therefore, the purpose of this study was to evaluate the effectiveness of unified transdiagnostic therapy on self-concept and psychological distress in students with depression symptoms. Method: The research method was semi-experimental with pre-test and post-test with control group. The statistical population consisted of all high school students with depressive symptoms in Shiraz in the academic year 2017-2018. The study sample consisted of 30 students with depressive symptoms who were selected by convenient sampling and were randomly assigned to experimental and control groups. The experimental group received the unified transdiagnostic therapy in 10 sessions of 90 minutes for three months, while the control group did not receive the intervention during the research process. Data were collected using the Mental Disorders Questionnaire (Drogatis et al., 1994), Self-concept Questionnaire (Pierce-Harris, 1969) and Depression Scale (Beck et al., 1994). Data were analyzed using univariate analysis of covariance and statistical software SPSS23. Results: The results of data analysis showed that the unified transdiagnostic therapy was effective on level of self-concept (F = 35.33