The research project outlined in this proposal aims to investigate the effectiveness of stabilizing group treatment as an add-on to conventional treatment, for patients with Post Traumatic Stress Disorder (PTSD) or dissociative disorders after childhood abuse. The investigators also aim to study psychophysiological markers associated with complex trauma and treatment, mechanisms of change involved in treatment, and which patient characteristics that predict positive outcome.

Patients with histories of repeated traumatization in childhood often display a wide array of symptoms described as complex traumatic stress disorder. This sequela involves a high degree of comorbid mental and somatic disturbances, and entails tremendous health care costs for society and suffering for the victims. Despite the prevalence and consequences of complex trauma, research on effective treatments is extremely limited. Expert clinicians suggest that initial treatment for these patients should focus on stabilization of symptoms through psychoeducation and skills - training, and some research has supported this advice. Offering such treatment as group therapy can be both cost - effective and give patients additional peer-support. The research project outlined in this proposal aims to investigate the effectiveness of stabilizing group treatment as an add-on to conventional treatment, for patients with PTSD or dissociative disorders after childhood abuse. This will be investigated in a randomized controlled design. The investigators also aim to discover psychophysiological markers associated with treatment, mechanisms of change involved in treatment, and what patient characteristics that predict outcome. The results may contribute to new knowledge about treatment of complex traumatization, as well as new and improved health services for a vulnerable patient group with little specialized treatment today.

The main aim of this project is to compare the effectiveness of stabilizing group treatment as an add-on to conventional individual therapy, to conventional individual therapy alone, in a randomized controlled design. This will be tested in two independent diagnostic groups: Patients with PTSD and patients with Dissociative disorders, both groups with reports of childhood abuse. The investigators will further investigate how level of dissociative symptoms influence treatment, how group climate influence symptoms, the relationship between individual and group therapy in combined treatment, and how treatment affects Heart Rate Variability. The investigators also seek to evaluate the treatment economically with a societal perspective, carrying out cost-utility analyses.

• The inclusion criteria will be similar to clinical practice to ensure the external validity of the research.

  • participants must report a history of childhood abuse
  • be between 18 and 65 years of age
  • have enough competence in Norwegian to be able to participate in a psychoeducational group.

• In the PTSD arm of the study patients must meet the criteria for a DSM - 5 diagnosis of Posttraumatic Stress Disorder.

• In the Dissociative-disorders arm of the study the patients must meet criteria for a DSM-5 diagnosis of Dissociative Identity Disorder (DID) or Dissociative Disorder Not Otherwise Specified (DDNOS).

Exclusion criteria will include:

1. Acute suicidality
2. Serious substance abuse interfering with treatment
3. Serious psychotic symptoms
4. Current life - crisis interfering with therapy (e.g. ongoing abuse, divorce, court case, somatic disease in spouse or children, etc.)
5. Neurological disease, mental disability or life threatening somatic disease. For the PTSD arm of the study an additional exclusion criteria will be that the patient meets the criteria for a dissociative disorder.