The Effectiveness of Combining Cognitive Processing Therapy with a Case Formulation Approach in the Treatment of Posttraumatic Stress Disorder - A Randomised Controlled Trial

Treatment Group One: CPT only Cognitive Processing Therapy is a recognised CBT based approach for the treatment of PTSD. It comprises 12 sessions of material that follows a manualised format developed by Resick, Monsoon and Chard (2007). Initial sessions provide a rationale for the approach and an overview of treatment. Psychoeducation about PTSD and the basics of cognitive theory are discussed, with the client completing an Impact Statement that assists in the identification of ‘stuck points’, or problematic thinking about the traumatic event. In subsequent sessions the connection between events, thoughts and feelings are introduced and applied to the Impact Statement. Now optional in CPT, clients can also write a detailed description of the event through a Trauma Account. Clients continue to work through their stuck points as they relate to the traumatic event, with the therapist using a variety of techniques including Socratic questioning and challenging questions about stuck points and problematic thinking. Later modules on safety, trust, power and control, esteem and intimacy all address beliefs about each theme. For the present study, up to 15 sessions of CPT will be offered in the CPT alone condition. Sessions will generally be conducted on a weekly basis face-to-face and on an individual basis. Sessions may be more frequent (twice weekly) depending on client preference and therapist discretion. Treatment Group Two - CPT + Case Formulation CPT+CF will include a case formulation approach based on the processes suggested by (Kuyken et al., 2009) which integrates clients’ experiences with relevant CBT research. As such the formulation will be in diagrammatic form, focusing on the client’s thoughts, feelings, physiological sensations and behaviour as it relates to the trauma event. In addition imagery will be utilised given symptoms often include strong visual images and flashbacks to the trauma. In order to individualise the formulation and ensure that other presenting issues are identified, past experiences, both distal and proximal events that might be relevant will be included (e.g., the experience of severe childhood bullying might have also influenced the unhelpful or core beliefs of a client who has also experienced domestic violence). Client’s capabilities and strengths are also examined. This explicit CF will be introduced in Session 1 and will be revisited as needed, especially in the context of treatment gains not being observed during therapy (as tracked by the weekly administration of the PCL and DASS-21). Thus this formulation can guide the therapist to barriers in treatment and help with decisions such as whether to target a particular comorbidity that might be interfering with treatment. The explicit goal of the CPT+CFT approach is to ensure a trauma-focus to therapy, thus where deviation from the CPT protocol occurs, the ultimate goal of treatment is to return to addressing PTSD symptoms. Where other interventions are introduced to assist with this goal (e.g., targeting of comorbid panic attacks that are interfering with engaging in trauma-specific work), these additional interventions will be CBT and evidence-based. All deviations from the CPT protocol will be documented using a form created for the purpose. This will include the nature of the deviation, the time spent and whether the deviations are considered minor or major. For the present study, up to 15 sessions of CPT will be offered in the CPT+CF condition. Sessions will generally be conducted on a weekly basis face-to-face and on an individual basis. Sessions may be more frequent (twice weekly) depending on client preference and therapist discretion. To ensure diagnostic reliability, all pretreatment diagnostic interviews and therapy sessions will be video/audiotaped and will be coded by a research assistant to ensure that the therapist is adhering to the components of each treatment session. By adopting this design the proposed research conforms to the gold standard for conducting treatment outcome research with traumatised samples (Foa & Meadows, 1997), and ensures the methodological rigour of the proposed project. Assessors who have no knowledge of the participants, treatment allocation or stage or treatment reached will be used at post and six-month follow up assessments. Assessors will conduct post treatment interviews and questionnaires with participants, and again at the six month mark. The majority of treatment for both groups will be conducted by the researcher, a registered psychologist trained in the CPT protocol and case formulation approach. When required, other therapists will be used for either treatment group. All other therapists will be currently undertaking clinical psychology training or have recently completed this training and undertaking a placement in the Flinders University Trauma Unit. Therapists will receive weekly supervision from Professor Nixon. The researcher will be located at Yarrow Place to provide on site therapy to Yarrow Place clients one day per week and will also provide therapy on site at the Trauma Unit at Flinders University Campus. Each session is anticipated to last 1 to 1.5 hours.