ABSTRACT

Background: Meta-analyses report that Cognitive Behavior Therapy (CBT), together with Eye Movement Desensitization and Reprocessing (EMDR), are the most studied and recommended treatments for PTSD. Most studies have focused on individual treatment and only a few on group psychotherapy treatments. The lack of randomized controlled studies on arts-based psychotherapy methods results in them not being recommended as viable treatments for trauma-related disturbances, even though case studies and qualitative studies have shown that they are helpful and appreciated by clients.

Aim: This PhD study aimed to investigate the efficacy of an arts-based psychotherapy method, phase-based trauma-focused Group Music and Imagery (Tf-GrpMI), in the treatment of women suffering from PTSD or CPTSD after being exposed to interpersonal trauma with physical, psychological and/or sexual abuse in childhood and/or adulthood.

Method: The PhD study was divided into two parts. Part one was a feasibility study using a mixed method design with repeated measurements and a qualitative analysis inspired by thematic analysis of the semi-structured interviews conducted after the treatment period ended. The feasibility study had a sample size of (n = 10). Part two was a randomized controlled study (RCT) with a parallel group design, treatment group versus waiting list control (WLC) group. The sample size was (n = 45). The participants received 12 weekly Tf-GrpMI sessions of 2,5 hours in length. They filled in self-rating scales before and after the intervention and at a three-month follow-up. The primary outcome was the treatment's efficacy on PTSD symptoms, measured with the checklist for DSM-5 (PCL-5) self-report scale. Secondary outcomes were anxiety, depression, dissociation, quality of life and the specific symptoms that, in addition to PTSD symptoms, are related to CPTSD, the disturbances in self-organization (DSO) symptoms: negative self-concept, affect dysregulation, and problems in relationships. Physiological measures of heart rate (HR), heart rate variability (HRV) and skin conductance (SC) were obtained before and after the intervention using a script-driven imagery method.

Result: Both the feasibility study and the RCT showed a significant reduction in PTSD symptoms, with large effect sizes (ES) as measured with Cohen's d. The secondary outcomes also changed significantly in a favourable direction with a medium to large ES. All the changes were sustained at the three months follow-up. The physiological measures showed a decreased HR and SC reactivity and an increased HRV after treatment compared to the WLC group. The results from semi-structured interviews in the feasibility study implied that the treatment was acceptable and that the participants felt helped by the arts-based psychotherapy method.

Conclusion: The findings indicate that Tf-GrpMI is a promising group psychotherapy method for women suffering from PTSD or CPTSD due to interpersonal trauma. However, further studies are warranted to support the results.