Intervention components, mediators, and mechanisms of change of Internet- and mobile-based interventions for post-traumatic stress disorder: protocol for a systematic review and meta-analysis

BACKGROUND: While Internet- and mobile-based interventions (IMIs) might possess the potential to increase access to evidence-based therapies for post-traumatic stress disorder (PTSD), comprehensive knowledge on active intervention components and change mechanisms underlying their efficacy is largely pending so far. The proposed systematic review and meta-analysis will systematically review the current status of research on the efficacy of IMIs for adult PTSD compared to active control conditions and identify active intervention components and mediators responsible for therapeutic change. METHODS: A systematic literature search (PsycINFO, Medline/PubMed, Embase, CENTRAL, ICTRP, and Web of Science) will be conducted using keywords targeting “PTSD” and “Internet- and mobile-based interventions”. Two independent researchers will retrieve studies eligible for inclusion and extract and evaluate data (design, population, outcomes, sample size, duration of intervention and follow-up, drop-out rate). Risk of bias will be assessed, and results will be synthesized qualitatively and evaluated meta-analytically when possible. DISCUSSION: The results of this systematic review and meta-analysis might further contribute to the development of IMIs for PTSD by highlighting intervention components and mediators associated with their efficacy. Knowledge about the active ingredients might ultimately lead to more effective interventions and treatment packages, with implications for clinical practice and dissemination of these rather novel interventions. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (CRD42019130314).