Efficacy of an Internet-based intervention with self-applied exposure therapy in virtual reality for people with panic disorder: study protocol for a randomized controlled trial

BACKGROUND: Due to several treatment barriers, many individuals with panic disorder do not receive evidence-based treatment. One promising option to narrow this treatment gap is Internet-based psychotherapy, which has been shown particularly effective in guided formats. Still, there remains room for improvement to make these digital therapies more accessible, cost-efficient, and aligned with best practices for in-person interventions (e.g., exposure). The smartphone app “Invirto – Treatment for Anxiety” offers digitally guided, evidence-based treatment of panic disorders including virtual reality (VR) for exposure therapy. The aim present study is to investigate the efficacy, safety, and acceptance of Invirto in comparison to a care-as-usual (CAU) control group. METHODS: We plan to conduct a randomized controlled trial with two conditions (intervention vs. CAU), three assessment times via online surveys (t0: baseline; t1: 3 months after baseline; t2: follow-up assessment 6 months after baseline), and a total of 128 participants with a clinical diagnosis of panic disorder (symptoms must be experienced ≥ 1 year). Recruitment will take place via email, phone, and the study website. The primary outcome will be the change in anxiety symptoms as measured by Beck’s Anxiety Inventory from t0 to t1. Secondary outcomes will be the change in anxiety symptoms (measured by the Panic and Agoraphobia Scale, PAS; Questionnaire on panic-related Anxieties, Cognitions and Avoidance, ACA), depressive symptoms (measured by the Beck-Depression-Inventory, BDI-II), treatment satisfaction (measured by the Client Satisfaction Questionnaire, CSQ-8; Treatment Adherence Perception Questionnaire, TAPQ-adapt; Positive and Negative Effects of Psychotherapy Scale, PANEPS-I), psychological flexibility (measured by the Acceptance and Action Questionnaire-II, AAQ-II), and dissociation during VR exposure (measured by an adapted version of the Peritraumatic Dissociative Experiences Questionnaire, PDEQ-adapt). Participants in the intervention group will receive access to the intervention (Invirto) right after t0, while the CAU group will receive access to Invirto after t1. We expect a larger change in both the primary and secondary outcomes from t0 to t1 in the intervention group in comparison to the CAU group. DISCUSSION: This study is one of the first to evaluate an Internet-based intervention for people with panic disorder that includes self-application of VR exposure therapy. The findings are expected to extend the body of knowledge about effective Internet-based treatment options for people with panic disorder. The empirical and clinical implications and the limitations of the study are discussed. TRIAL REGISTRATION: DRKS00027585 (www.drks.de/drks_web/), date of registration: 13 January 2022. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-023-07536-1.