Assessing the effectiveness of internet-based interventions for mental health outcomes: an umbrella review.

Internet-based interventions (IBIs) for behavioural health have been prevalent for over two decades, and a growing proportion of individuals with mental health concerns prefer these emerging digital alternatives. However, the effectiveness and acceptability of IBIs for various mental health disorders continue to be subject to scholarly debate. We performed an umbrella review of meta-analyses (MAs), conducting literature searches in PubMed, Web of Science, Embase, Cochrane and Ovid Medline from their inception to 17 January 2023. A total of 87 MAs, reporting on 1683 randomised controlled trials and 295 589 patients, were included. The results indicated that IBIs had a moderate effect on anxiety disorder (standardised mean difference (SMD)=0.53, 95% CI 0.44 to 0.62) and post-traumatic stress disorder (PTSD) (SMD=0.63, 95% CI 0.38 to 0.89). In contrast, the efficacy on depression (SMD=0.45, 95% CI 0.39 to 0.52), addiction (SMD=0.23, 95% CI 0.16 to 0.31), suicidal ideation (SMD=0.23, 95% CI 0.16 to 0.30), stress (SMD=0.41, 95% CI 0.33 to 0.48) and obsessive-compulsive disorder (SMD=0.47, 95% CI 0.22 to 0.73) was relatively small. However, no significant effects were observed for personality disorders (SMD=0.07, 95% CI -0.13 to 0.26). Our findings suggest a significant association between IBIs and improved mental health outcomes, with particular effectiveness noted in treating anxiety disorders and PTSD. However, it is noteworthy that the effectiveness of IBIs was impacted by high dropout rates during treatment. Furthermore, our results indicated that guided IBIs proved to be more effective than unguided ones, playing a positive role in reducing dropout rates and enhancing patient adherence rates. PROSPERO registration number: CRD42023417366.