References

• Andersson, G., & Titov, N. (2014). Advantages and limitations of Internet-based interventions for common mental disorders. World Psychiatry, 13(1), 4–14.
   PubMed Web of Science ®Google Scholar
• Assink, M., & Wibbelink, C. J. (2016). Fitting three-level meta-analytic models in R: A step-by-step tutorial. The Quantitative Methods for Psychology, 12(3), 154–174.
   Web of Science ®Google Scholar
• Barak, A., Klein, B., & Proudfoot, J. G. (2009). Defining internet-supported therapeutic interventions. Annals of Behavioral Medicine, 38(1), 4–17.
   PubMed Web of Science ®Google Scholar
• Barbui, C., & Tansella, M. (2013). Mental disorders and conditions specifically related to stress. Epidemiology and Psychiatric Sciences, 22(3), 195–196.
   PubMed Web of Science ®Google Scholar
• Baron, R. M., & Kenny, D. A. (1986). The moderator-mediator variable distinction in social psychological research. Conceptual, strategic, and statistical considerations. Journal of Personality and Social Psychology, 51(6), 1173–1182.
   PubMed Web of Science ®Google Scholar
• Baumeister, H., Reichler, L., Munzinger, M., & Lin, J. (2014). The impact of guidance on Internet-based mental health interventions - A systematic review. Internet Interventions, 1(4), 205–215.
   Google Scholar
• Beatty, L., Koczwara, B., & Wade, T. (2016). Evaluating the efficacy of a self-guided Web-based CBT intervention for reducing cancer-distress: A randomised controlled trial. Supportive Care in Cancer, 24(3), 1043–1051.
   PubMed Web of Science ®Google Scholar
• Bell, E. C., Marcus, D. K., & Goodlad, J. K. (2013). Are the parts as good as the whole? A meta-analysis of component treatment studies. Journal of Consulting and Clinical Psychology, 81(4), 722–736.
   PubMed Web of Science ®Google Scholar
• Benight, C. C., Shoji, K., Yeager, C. M., Weisman, P., & Boult, T. E. (2018). Predicting change in posttraumatic distress through change in coping self-efficacy after using the my trauma recovery eHealth intervention. JMIR Mental Health, 5(4), e10309.
   PubMed Web of Science ®Google Scholar
• Borenstein, M., Hedges, L., Higgins, J., & Rothstein, H. (2009). Introduction to meta-analysis. Hoboken, NJ: John Wiley & Sons.
   Google Scholar
• Brewin, C. R., Andrews, B., & Valentine, J. D. (2000). Meta-analysis of risk factors for posttraumatic stress disorder in trauma-exposed adults. Journal of Consulting & Clinical Psychology, 68(5), 748–766.
   PubMed Web of Science ®Google Scholar
• Bryant, R. A. (2019). Post-traumatic stress disorder: A state-of-the-art revidew of evidence and challenges. World Psychiatry, 18(3), 259–269.
   PubMed Web of Science ®Google Scholar
• Burns, T. (2009). End of the road for treatment-as.usual studies? The British Journal of Psychiatry, 195(1), 5–6.
   PubMed Web of Science ®Google Scholar
• Carlbring, P., Andersson, G., Cuijpers, P., Riper, H., & Hedman-Lagerlöf, E. (2018). Internet-based vs. face-to-face cognitive behavior therapy for psychiatric and somatic disorders: An updated systematic review and meta-analysis. Cognitive Behaviour Therapy, 47(1), 1–18.
   PubMed Web of Science ®Google Scholar
• Cheung, M. (2015). metaSEM: An R package for meta-analysis using structural equation modeling. Frontiers in Psychology, 5, 1521.
   PubMed Web of Science ®Google Scholar
• Cheung, M., & Chan, W. (2009). A two-stage approach to synthesizing covariance matrices in meta-analytic structural equation modeling. Structural Equation Modeling, 16(1), 28–53.
   Web of Science ®Google Scholar
• Cieslak, R., Benight, C. C., Rogala, A., Smoktunowicz, E., Kowalska, M., Zukowska, K., … Luszczynska, A. (2016). Effects of internet-based self-efficacy intervention on secondary traumatic stress and secondary posttraumatic growth among health and human services professionals exposed to indirect trauma. Frontiers in Psychology, 7, 1009.
   PubMed Web of Science ®Google Scholar
• Clausen, A. N., Thelen, J., Francisco, A. J., Bruce, J., Martin, L., McDowd, J., & Aupperle, R. L. (2019). Computer-based executive function training for combat veterans with PTSD: A pilot clinical trial assessing feasibility and predictors of dropout. Frontiers in Psychiatry, 10, 62.
   PubMed Web of Science ®Google Scholar
• Cohen, J. (1988). Statistical power analysis for the behavioral sciences. Hillsdale: Lawrence Erlbaum.
   Google Scholar
• Cuijpers, P., Cristea, I. A., Karyotaki, E., Reijnders, M., & Hollon, S. D. (2017). Component studies of psychological treatments of adult depression: A systematic review and meta-analysis. Psychotherapy Research, 29(1), 15–29.
   PubMed Web of Science ®Google Scholar
• Cuijpers, P., Reijnders, M., & Huibers, M. J. H. (2019). The role of common factors in psychotherapy outcomes. Annual Review of Clinical Psychology, 15(1), 207–231.
   PubMed Web of Science ®Google Scholar
• Cusack, K., Jonas, D. E., Forneris, C. A., Wines, C., Sonis, J., Middleton, J. C., … Gaynes, B. N. (2016). Psychological treatments for adults with posttraumatic stress disorder: A systematic review and meta-analysis. Clinical Psychology Review, 43, 128–141.
   PubMed Web of Science ®Google Scholar
• de Kleine, R. A., Woud, M. L., Ferentzi, H., Hendriks, G. J., Broekman, T. G., Becker, E. S., & Van Minnen, A. (2019). Appraisal-based cognitive bias modification in patients with posttraumatic stress disorder: A randomised clinical trial. European Journal of Psychotraumatology, 10(1), 1625690.
   Google Scholar
• Dickersin, K. (1990). The existence of publication bias and risk factors for its occurence. JAMA, 263(10), 13.
   PubMed Web of Science ®Google Scholar
• Domhardt, M., Ebert, D. D., & Baumeister, H. (2018). Internet- und mobile-basierte Interventionen. In C. Kohlmann, C. Salewski, & M. A. Wirtz (Eds.), Psychologie in der Gesundheitsförderung (pp. 397–410). Bern: Hogrefe.
   Google Scholar
• Domhardt, M., Cuijpers, P., Ebert, D. D., & Baumeister, H. (accepted). More light? Opportunities and pitfalls in digitalized psychotherapy process research. Frontiers in Psychology.
   Web of Science ®Google Scholar
• Domhardt, M., Geßlein, H., von Rezori, R. E., & Baumeister, H. (2019). Internet- and mobile-based interventions for anxiety disorders: A meta-analytic review of intervention components. Depression and Anxiety, 36(3), 213–224.
   PubMed Web of Science ®Google Scholar
• Domhardt, M., Steubl, L., & Baumeister, H. (2018). Internet- and mobile-based interventions for mental and somatic conditions in children and adolescents. Zeitschrift Für Kinder- Und Jugendpsychiatrie Und -Psychotherapie, 48(1), 1–14.
   Web of Science ®Google Scholar
• Domhardt, M., Steubl, L., Boettcher, J., Buntrock, C., Karyotaki, E., Ebert, D. D., … Baumeister, H. (2021). Mediators and mechanisms of change in Internet- and mobile-based interventions for depression: Systematic review and formulation of an integrative psychological model. Clinical Psychology Review, 83, 101953.
   PubMed Web of Science ®Google Scholar
• Duval, S., & Tweedie, R. (2000). Trim and fill: A simple funnel-plot-based method of testing and adjusting for publication bias in meta-analysis. Biometrics, 56(2), 455–463.
   PubMed Web of Science ®Google Scholar
• Egger, M., Smith, G. D., Schneider, M., & Minder, C. (1997). Bias in meta-analysis detected by a simple, graphical test. BMJ, 315(7109), 629–634.
   PubMed Web of Science ®Google Scholar
• Egger, M., Zellweger-Zähner, T., Schneider, M., Junker, C., Lengeler, C., & Antes, G. (1997). Language bias in randomised controlled trials published in English and German. Lancet, 350(9074), 326–329.
   PubMed Web of Science ®Google Scholar
• Eisma, M. C., Boelen, P. A., van den Bout, J., Strobe, W., Schuth, H. A. W., Lancee, J., & Strobe, M. S. (2015). Internet-based exposure and behavioral activation for complicated grief and rumination: A randomized controlled trial. Behavior Therapy, 46(6), 729–748.
   PubMed Web of Science ®Google Scholar
• Finch, J., Ford, C., Grainger, L., & Meiser-Stedman, R. (2020). A systematic review of the clinician related barriers and facilitators to the use of evidence-infomred interventions for post traumatic stress. Journal of Affective Disorders, 263, 175–186.
   PubMed Web of Science ®Google Scholar
• Furukawa, T. A., Karyotaki, E., Suganuma, A., Pompoli, A., Ostinelli, E. G., Cipriani, A., … Efthimiou, O. (2018). Dismantling, personalising and optimising internet cognitive-behavioural therapy for depression: A study protocol for individual participant data component network meta-analysis. BMJ Open, 8(11), e026137.
   Web of Science ®Google Scholar
• Gallagher, M. W., & Resick, P. A. (2012). Mechanisms of change in cognitive processing therapy and prolonged exposure therapy for ptsd: Preliminary evidence for the differential effects of hopelessness and habituation. Cognitive Therapy and Research, 36(6), 750–755.
   Web of Science ®Google Scholar
• Guyatt, G., Oxman, A., Vist, G., Kunz, R., Falck-Ytter, Y., Alonso-Coello, P., & Schünemann, H. (2008). GRADE: An emerging consensus on rating quality of evidence and strength of recommendations. British Medical Journal, 336(7650), 924–926.
   PubMed Web of Science ®Google Scholar
• Hayes, A. F. (2013). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach. New York: Guilford Press.
   Google Scholar
• Higgins, J. P., Altman, D. G., Gøtzsche, P. C., Jüni, P., Moher, D., & Oxman, A. D. (2011). The Cochrane Collaboration ’ s tool for assessing risk of bias in randomised trials. BMJ, 343(oct18 2), d5928–d5928.
   PubMed Web of Science ®Google Scholar
• Higgins, J. P. T., & Green, S. (2011). Cochrane handbook for systematic reviews of interventions. Retrieved from https://handbook.cochrane.org/
   Google Scholar
• Horgan, Á., & Sweeney, J. (2010). Young students’ use of the internet for mental health information and support. Journal of Psychiatric and Mental Health Nursing, 17(2), 117–123.
   PubMed Web of Science ®Google Scholar
• Kahn, J. R., Collinge, W., & Soltysik, R. (2016). Post-9/11 veterans and their partners improve mental health outcomes with a self-directed mobile and web-based wellness training program: A randomized controlled trial. Journal of Medical Internet Research, 18(9), e255.
   PubMed Web of Science ®Google Scholar
• Kangaslampi, S., & Peltonen, K. (2019). Mechanisms of change in psychological interventions for posttraumatic stress symptoms: A systematic review with recommendations. Current Psychology. Advance online publication. doi:10.1007/s12144-019-00478-5
   PubMed Web of Science ®Google Scholar
• Karlsson, P., & Bergmark, A. (2015). Compared with what? An analysis of control-group types in Cochrane and Campbell reviews of psychosocial treatment efficacy with substance use disorders. Addiction, 110(3), 420–428.
   PubMed Web of Science ®Google Scholar
• Karyotaki, E., Kleiboer, A., Smit, F., Turner, D. T., Pastor, A. M., Andersson, G., … Cuijpers, P. (2015). Predictors of treatment dropout in self-guided web-based interventions for depression: An “individual patient data” meta-analysis. Psychological Medicine, 45(13), 2717–2726.
   PubMed Web of Science ®Google Scholar
• Kazantzis, N., Luong, H. K., Usatoff, A. S., Impala, T., Yew, R. Y., & Hofmann, S. G. (2018). The processes of cognitive behavioral therapy: A review of meta-analyses. Cognitive Therapy and Research, 42(2), 349–357.
   Google Scholar
• Kazdin, A. E. (2007). Mediators and mechanisms of change in psychotherapy research. Annual Review of Clinical Psychology, 3(1), 1–27.
   PubMed Web of Science ®Google Scholar
• Kazdin, A. E., & Nock, M. K. (2003). Delineating mechanisms of change in child and adolescent therapy: Methodological issues and research recommendations. Journal of Child Psychology & Child Psychiatry, 44(8), 1116–1129.
   PubMed Web of Science ®Google Scholar
• Kraemer, H. C., Wilson, G. T., Fairburn, C. G., & Agras, W. S. (2002). Mediators and moderators of treatment effects in randomized clinical trials. Archives of General Psychiatry, 59(10), 877–883.
   PubMed Web of Science ®Google Scholar
• Krupnick, J. L., Green, B. L., Amdur, R., Alaoui, A., Belouali, A., Roberge, E., … Dutton, M. A. (2017). An internet-based writing intervention for PTSD in veterans: A feasibility and pilot effectiveness trial. Psychological Trauma, 9(4), 461–470.
   PubMed Web of Science ®Google Scholar
• Kuester, A., Niemeyer, H., & Knaevelsrud, C. (2016). Internet-based interventions for posttraumatic stress: A meta-analysis of randomized controlled trials. Clinical Psychology Review, 43, 1–16.
   PubMed Web of Science ®Google Scholar
• Landis, J. R., & Koch, G. G. (1977). The measurement of observer agreement for categorical data. Biometrics, 33(1), 159.
   PubMed Web of Science ®Google Scholar
• Lemmens, L. H. J. M., Müller, V. N. L. S., Arntz, A., & Huibers, M. J. H. (2016). Mechanisms of change in psychotherapy for depression: An empirical update and evaluation of research aimed at identifying psychological mediators. Clinical Psychology Review, 50, 95–107.
   PubMed Web of Science ®Google Scholar
• Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gøtzsche, P. C., Ioannidis, J. P. A., … Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: Explanation and elaboration. PLoS Medicine, 6(7), e1000100.
   PubMed Web of Science ®Google Scholar
• Littleton, H., Grills, A. E., Kline, K. D., Schoemann, A. M., & Dodd, J. C. (2016). The from survivor to thriver program: RCT of an online therapist-facilitated program for rape-related PTSD. Journal of Anxiety Disorders, 43, 41–51.
   PubMed Web of Science ®Google Scholar
• Lorenz, P., Schindler, L., Steudte-Schmiedgen, S., Weidner, K., Kirschbaum, C., & Schellong, J. (2019). Ecological momentary assessment in posttraumatic stress disorder and coping. An eHealth study protocol. European Journal of Psychotraumatology, 10(1), 1654064.
   PubMed Web of Science ®Google Scholar
• Lorenzo-Luaces, L., & DeRubeis, R. J. (2018). Miles to go before we sleep: Advancing the understanding of psychotherapy by modeling complex processes. Cognitive Therapy and Research, 42(2), 212–217.
   Web of Science ®Google Scholar
• McMillen, C., North, C., Mosley, M., & Smith, E. (2002). Untangling the psychiatric comorbidity of posttraumatic stress disorder in a sample of flood survivors. Comprehensive Psychiatry, 43(6), 478–485.
   PubMed Web of Science ®Google Scholar
• Morrison, A., Polisena, J., Husereau, D., Moulton, K., Clark, M., Fiander, M., … Rabb, D. (2012). The effect of English-language restriction on systematic review-based meta-analyses: A systematic review of empirical studies. International Journal of Technology Assessment in Health Care, 28(2), 138–144.
   PubMed Web of Science ®Google Scholar
• Muthén, L. K., & Muthén, B. O. (1998–2017). Mplus user’s guide. Los Angeles: Author.
   Google Scholar
• Niles, A. N., Woolley, J. D., Tripp, P., Pesquita, A., Vinogradov, S., Neylan, T. C., & O’Donovan, A. (2020). Randomized controlled trial testing mobile-based attention-bias modification for posttraumatic stress using personalized word stimuli. Clinical Psychological Science, 8(4), 756–772.
   Google Scholar
• Possemato, K., Johnson, E. M., Emery, J. B., Wade, M., Acosta, M., Marsch, L., … Maisto, S. (2019). A pilot study comparing peer supported web-based CBT to self-managed web CBT for primary care veterans with PTSD and hazardous alcohol use. Psychiatric Rehabilitation Journal, 42(3), 305–313.
   PubMed Web of Science ®Google Scholar
• Possemato, K., Kuhn, E., Johnson, E., Hoffman, J., Owen, J., Kanuri, N., … Brooks, E. (2016). Using PTSD coach in primary care with and without clinician support: A pilot randomized controlled trial. General Hospital Psychiatry, 38, 94–98.
   PubMed Web of Science ®Google Scholar
• Preacher, K. J., & Hayes, A. F. (2004). SPSS and SAS procedures for estimating indirect effects in simple mediation models. Behavior Research Methods, Instruments, & Computers, 36(4), 717–731.
   PubMedGoogle Scholar
• R Core Team. (2017). R: A language and environment for statistical computing. Retrieved from https://www.r-project.org
   Google Scholar
• Rothbaum, B. O., & Schwarz, A. C. (2002). Exposure therapy for posttraumatic stress disorder. American Journal of Psychotherapy, 56(1), 59–75.
   PubMed Web of Science ®Google Scholar
• Roy, M. J., Costanzo, M. E., Highland, K. B., Olsen, C., Clayborne, D., & Law, W. (2017). An app a day keeps the doctor away: Guided education and training via smartphones in subthreshold post traumatic stress disorder. Cyberpsychology, Behavior and Social Networking, 20(8), 470–478.
   PubMed Web of Science ®Google Scholar
• Sayer, N. A., Noorbaloochi, S., Frazier, P. A., Pennebaker, J. W., Orazem, R. J., Schnurr, P. P., … Litz, B. T. (2015). Randomized controlled trial of online expressive writing to address readjustment difficulties among U.S. Afghanistan and Iraq war veterans. Journal of Traumatic Stress, 28(5), 381–390.
   PubMed Web of Science ®Google Scholar
• Schnyder, U., Ehlers, A., Elbert, T., Foa, E. B., Gersons, B. P. R., Resick, P. A., … Cloitre, M. (2015). Psychotherapies for PTSD: What do they have in common? European Journal of Psychotraumatology, 6(1), 28186.
   PubMed Web of Science ®Google Scholar
• Sijbrandij, M., Kunovski, I., & Cuijpers, P. (2016). Effectiveness of internet-delivered cognitive behavioral therapy for posttraumatic stress disorder: A systematic review and meta-analysis. Depression and Anxiety, 33(9), 783–791.
   PubMed Web of Science ®Google Scholar
• Simblett, S., Birch, J., Matcham, F., Yaguez, L., & Morris, R. (2017). A systematic review and meta-analysis of e-Mental health interventions to treat symptoms of posttraumatic stress. JMIR Mental Health, 4(2), e14.
   PubMed Web of Science ®Google Scholar
• Spence, J., Titov, N., Johnston, L., Jones, M. P., Dear, B. F., & Solley, K. (2014). Internet-based trauma-focused cognitive behavioral therapy for PTSD with and without exposure components: A randomised controlled trial. Journal of Affective Disorders, 162, 73–80.
   PubMed Web of Science ®Google Scholar
• Steele, R. M., Mummery, W. K., & Dwyer, T. (2007). Examination of program exposure across intervention delivery modes: Face-to-face versus internet. International Journal of Behavioral Nutrition and Physical Activity, 4(1), 7.
   PubMedGoogle Scholar
• Steubl, L., Sachser, C., Baumeister, H., & Domhardt, M. (2019). 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. Systematic Reviews, 8(1), 265.
   PubMed Web of Science ®Google Scholar
• Stevens, N. R., Holmgreen, L., Walt, L., Gengler, R., & Hobfoll, S. E. (2017). Web-based trauma intervention for veterans has physical payoff in randomized controlled trial. Psychological Trauma, 9(1), 42–50.
   PubMedGoogle Scholar
• The Cochrane Collaboration. (2014). Review Manager (RevMan). Retrieved from https://revman.cochrane.org
   Google Scholar
• Wagner, B., Schulz, W., & Knaevelsrud, C. (2012). Efficacy of an Internet-based intervention for posttraumatic stress disorder in Iraq: A pilot study. Psychiatry Research, 195(1–2), 85–88.
   PubMed Web of Science ®Google Scholar
• Wampold, B., Imel, Z., Laska, K., Benish, S., Miller, S., Flückiger, C., … Budge, S. (2010). Determining what works in the treatment of PTSD. Clinical Psychology Review, 30(8), 923–933.
   PubMed Web of Science ®Google Scholar
• Wampold, B., Mondin, G., Moody, M., Stich, F., Benson, K., & Ahn, H. N. (1997). A meta-analysis of outcome studies comparing bona fide psychotherapies: Empirically, “all must have prizes”. Psychological Bulletin, 122(3), 203–215.
   Web of Science ®Google Scholar
• Xu, W., Wang, J., Wang, Z., Li, Y., Yu, W., Xie, Q., … Maercker, A. (2016). Web-based intervention improves social acknowledgement and disclosure of trauma, leading to a reduction in posttraumatic stress disorder symptoms. Journal of Health Psychology, 21(11), 2695–2708.
   PubMed Web of Science ®Google Scholar