Comparing the Effects of Schema Therapy and Acceptance and Commitment Therapy on Experiential Avoidance in Patients with Dysthymic Disorder

Depression is a chronic psychological disorder characterized by a depressed mood on most days and hours. This disorder is among the most common psychological disorders in our country. There are various psychotherapies available to help these patients and are used. One of these interventions, effective in multiple studies on several symptoms of depression, is Schema Therapy (ST). ST can significantly reduce depression symptoms and suicidal ideation in depressed patients. The present study aimed to compare the effects of ST and Acceptance and Commitment Therapy (ACT) on Experienced Avoidance (EA) in patients with depression.

This was a quasi–experimental study with pretest–posttest, follow–up, and a control group design. The study's statistical population included all individuals referring to counseling centers and psychological services of Noshahr and Chalous Cities, Iran, in 2019 who received a diagnosis of depression in clinical evaluation by a psychologist. The sample consisted of 45 depressed individuals selected by the purposive sampling method. They were randomly assigned to three ACT, ST, and control groups. The sample size was calculated based on similar studies considering the effect size of 0.40, the confidence level of 0.95, the test power of 0.80, and the loss rate of 10 percent for each group of 15 subjects. Initially, all research groups were pretested; then, the experimental groups received 10 ninety–minute sessions ACT and ST. After the end of the training sessions, all research groups were tested again, and after three months of post–test implementation, the follow–up stage was performed. The inclusion criteria were under 60 years of age, diploma and higher educational levels, dysphoria diagnosis based on the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM–5) criteria and clinical interview, the lack of personality disorder, and satisfaction for participation. The exclusion criteria included not observing the group rules stated in the first session and absence from more than two sessions. Ethical considerations observed in the research included justifying the research so that before implementation, the purpose of the study and other conditions for patients with depression was described, such as that participation in the research is entirely optional and the lack of participation will not affect their healthcare process. The information will remain confidential with the researcher. Then, the informed consent form was obtained from them, and the patients completed all questionnaires. The instruments used in this study were Second Edition Depression Inventory (Beck, 2000) and Experimental Avoidance Questionnaire (Gamz et al., 2011). The collected data were analyzed by repeated–measure Analysis of Variance (ANOVA) in SPSS at the significance level of 0.05.

The obtained results indicated that ACT and ST effectively reduced the components of EA in patients with depression (p<0.001). Furthermore, ACT further reduced the features of EA compared to ST (p<0.001).

According to the results concerning the greater effectiveness of ACT on patients with depression, this treatment is recommended to reduce EA in these patients.