Phase-based psychotherapy as a treatment for dissociative identity disorder co-morbid with major depressive disorder

32nd International Congress of Psychology, 18‐23 July 2021 Prague, Czech Republic (Virtual) ; The single participant case study highlights the treatment and successful outcome of a 41-year-old Turkish female with a history of complex trauma presenting with Dissociative Identity Disorder (DID) and major depressive disorder and somatization. The treatment included a trauma-informed Phase-Based Psychotherapy (PBT) as recommended by the International Society for the Study of Trauma and Dissociation for treating DID. The patient required an intensive treatment plan for a number of reasons. I completed the treatment in 9 days with intensified interviews. However, there is no published study showing that PBT is being applied extensively. This study determines the efficacy of intensive PBT intervention on DID. Significant symptom improvements were realized post treatment across all measured domains of functioning, including dissociative symptoms, depression and wellbeing skills and somatization. Moreover, the client no longer met criteria for DID, major depressive disorder and somatization.