Internet-based cognitive behavioral therapy versus internet-based modified present-centered therapy for world trade center responders and survivors with posttraumatic stress disorder: rationale and design of a randomized controlled trial

Hannah R. Brinkman, Mary L. Kowalchyk, Leah Cahn, Cindy J. Aaronson, Maria Böttche, Candice Presseau, John C. Markowitz, Brett T. Litz, Laura Huckins, Rachel Yehuda, Christine Knaevelsrud, Robert H. Pietrzak, Adriana Feder


Background: Nearly two decades following the 9/11/2001 world trade center (WTC) attacks, a substantial proportion of WTC rescue and recovery workers (“responders”) and WTC survivors continue to experience WTC-related posttraumatic stress disorder (PTSD) symptoms. Internet-based cognitive behavioral therapies (I-CBT) are short-term, evidence-based, scalable treatments with the potential to reach large numbers of symptomatic WTC workers and survivors. However, no I-CBT studies have been conducted in the WTC cohort.

Methods: This report describes the rationale and design of an ongoing randomized controlled trial comparing integrative testimonial therapy (ITT), an I-CBT, to an active comparison treatment, internet-based modified present-centered therapy. The primary aim is to evaluate the efficacy of ITT in mitigating WTC-related PTSD symptoms in WTC responders and survivors with full or subthreshold WTC-related PTSD. The efficacy of ITT in reducing comorbid depressive and anxiety symptoms, and improving functioning, quality of life, and post-traumatic growth will additionally be evaluated. Saliva samples are also collected to explore genetic and epigenetic biomarkers of treatment response.

Conclusions: This is the first I-CBT trial to compare ITT to a credible and active treatment, controlling for critical third-variable explanations of superiority (e.g., non-specific therapy effects). This RCT bridges an important research gap in the rising field of I-CBT interventions and adds to the literature on the design of trials investigating evidence-based treatments for PTSD in WTC- and other trauma-affected populations. 

Trial registration: This trial was registered on on May 16, 2017 (NCT03154151).


Posttraumatic stress disorder, Internet intervention, Online therapy, 9/11, World trade center

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