A randomized controlled trial testing theory-driven enhancements to increase the efficacy of and engagement in a brief cognitive-behavioural therapy text-message intervention for co-occurring posttraumatic stress disorder symptoms and alcohol misuse.

Objective: Engaging individuals with co-occurring posttraumatic stress disorder (PTSD) and alcohol misuse (AM) in effective treatments is difficult. Brief, self-directed approaches that deliver empirically supported intervention techniques, such as cognitive-behavioural therapy (CBT) strategies, via technology may be effective and easier-to-access alternatives to traditional in-person therapy approaches for PTSD + AM. This paper describes the protocol for an intervention development study (NCT05372042) that evaluates a text-message intervention combining CBT texts with techniques from cognitive psychology (message framing) and social psychology (growth mindsets) for treatment of PTSD + AM.

Method: The study uses a 3 (message framing: gain vs. loss vs. no framing) × 2 (mindset: growth mindsets vs. not) factorial design to test enhancements to CBT texts. Individuals age 18+, who report symptoms of PTSD and AM, will be recruited to participate. Participants will complete screening, verification, and baseline measures. They will be randomized to condition and receive 3 text messages per week for 4 weeks. Participants will be assessed at post-, 1-, and 3-month follow-up.

Results: Analyses will evaluate whether framing and growth mindsets enhance the efficacy of CBT texts. A priori decision rules will be applied to select the intervention condition that is both the most effective and the simplest, which will be tested in a follow-up randomized controlled trial.

Conclusions: This study will identify the simplest, most efficacious CBT intervention for PTSD + AM. Its use of cognitive and social psychology-based enhancement and of a factorial decision can serve as examples of how to enhance and increase engagement in brief, self-directed CBT interventions.