Investigation of the effect of Dialectical Behavioral Therapy Skill Training on individuals with generalized anxiety disorder: A mixed method study

The aim of this thesis is to examine the effectiveness of Dialectical Behavior Therapy Skills Training (DBT-ST) on individuals with generalized anxiety disorder (GAD). For this purpose, an explanatory sequential design of mixed methods research was used. The study consists of interconnected and sequential quantitative and qualitative research phases. In the first phase, 24 female university students aged between 20-37 who were diagnosed with generalized anxiety disorder were randomly assigned to 12 experimental and 12 wait-listed control groups. Dialectical Behavior Therapy Skills Training was applied to the experimental group for 12 weeks, while the control group did not receive any application. Three measurements were taken from the participants using self-report tools before the intervention, at the end of the intervention and two months after the completion of the intervention. The quantitative data were analyzed using Two-Factor ANOVA for Mixed Measures. The results indicated that, after DBT-ST, participants in the experimental group showed decreased levels of generalized anxiety disorder, difficulties in emotion regulation, and interpersonal problems, while increased levels of mindfulness and distress tolerance. These improvements were maintained in the two-month follow-up assessment. No significant difference was found in the waiting list control group. In the second phase of the study, which is the qualitative research; interviews were conducted with five individuals who participated in the skills training for twelve weeks and selected based on the purposeful sampling method and volunteering. The data were analyzed with the Interpretive Phenomenological Analysis method. As a result of the analysis, the participants' statements consisted of three superordinate themes as "Living with Anxiety", "My DBT-ST Experience" and "My New Guide: DBT" and fifteen sub-themes covered by these themes. After the training, the participants shared their experiences with generalized anxiety disorder as well as their experiences with the mindfulness, emotion regulation, interpersonal relationships and distress tolerance of the training in detail. They stated that all the skills learned contributed the reduction of generalized anxiety disorder symptoms. As a result, it is seen that the quantitative and qualitative findings of the study are consistent, complement each other and that Dialectical Behavior Therapy Skills Training has a positive effect on individuals diagnosed with generalized anxiety disorder. This study is the first to examine the effect of DBT-ST on individuals with generalized anxiety disorder using a mixed methods approach. Based on the research findings, it is anticipated that Dialectical Behavior Therapy Skills Training may be an alternative therapeutic approach in the treatment of individuals with generalized anxiety disorder.