An Evaluation of Stepped Care for the Treatment of Posttraumatic Stress Disorder

Author: Larissa Roberts

Roberts, Larissa, 2023 An Evaluation of Stepped Care for the Treatment of Posttraumatic Stress Disorder, Flinders University, College of Education, Psychology and Social Work

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There is a pressing need to develop more efficient delivery systems to improve the accessibility of evidence-based treatments for PTSD. Stepped care approaches can increase the accessibility of treatment by matching clients to an intervention level that suits their current needs. Clients typically start with a low-intensity therapy (such as a self-guided therapy) and then can be “stepped up” to a higher-intensity therapy as required. As such, clinicians can maximise the impact of their time and skills. However, limited literature has evaluated stepped care for PTSD. This thesis advances this literature, first by conducting a systematic review and meta-analysis of stepped care approaches for PTSD. Then based on these findings, I developed and evaluated an online stepped care treatment approach for PTSD via a pilot study and randomised controlled trial (RCT).

The systematic review identified eight articles on stepped care prevention and only four articles on stepped care treatment for adults and adolescents/children with PTSD. The approaches were found to be as efficacious, acceptable, and more cost-effective compared to active and passive controls. However, interpretations were tempered by high statistical heterogeneity, risk of bias, and inconsistent use of recommended evidence-based treatments. Only two studies evaluating stepped care treatment approaches for adults were identified, justifying the need for further development of new stepped care treatment approaches for PTSD.

Following this review, I developed an online stepped care approach using two previously unpaired treatments, This Way Up (TWU; an online self-guided therapy) and Cognitive Processing Therapy (CPT; a well-established standard format therapy), adopting pre-specified criteria for stepping up between treatment steps. Initial testing of this approach in an open trial among 38 adults with PTSD revealed that PTSD, depression, and quality of life significantly improved across time (baseline, post-treatment, 3-month follow-up), and on average, most participants achieved good-end state functioning. Both treatments were rated as acceptable by participants. These findings indicated that a larger RCT of the stepped care approach was warranted.

Finally, an RCT was conducted to evaluate the stepped care approach compared to CPT delivered via telehealth among 84 adults with PTSD and subthreshold PTSD (42 in each group). Overall, stepped care cost less than CPT in terms of clinician time, but CPT was more acceptable than TWU and had less dropout. Both groups also had significant improvements in PTSD, depression, and quality of life over time (baseline, post-treatment, 3-month follow-up, 6-month follow-up); however, better outcomes were observed in the CPT group compared to stepped care. Participants with high PTSD severity, older age, and high readiness for change had superior treatment outcomes when they started with CPT compared to TWU in stepped care.

Taken together, these findings indicate that the stepped care approach was feasible, even among participants with high symptom severity and complexities. However, further research is needed to identify which clients should be offered the approach and at what treatment step. With further tailoring, stepped care has the potential to increase the accessibility of evidence-based treatments for PTSD while maximising treatment outcomes.

Keywords: posttraumatic stress disorder, PTSD, trauma, stepped care, treatment, telehealth, Cognitive Processing Therapy, This Way Up

Subject: Psychology thesis

Thesis type: Doctor of Philosophy
Completed: 2023
School: College of Education, Psychology and Social Work
Supervisor: Professor Reg Nixon