Efficacy of Internet-Based Self-Help Interventions for Irritable Bowel Syndrome: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder that reduces quality of life and causes a heavy medical burden. Internet-based self-help interventions are flexible and scalable, showing potential for IBS symptom improvement, but relevant evidence is fragmented and lacks systematic review. Objective: This systematic review aimed to comprehensively evaluate the effects of internet-based self-help interventions on symptom severity, quality of life, and visceral sensitivity, as well as comorbid depressive and anxiety symptoms, in individuals with IBS. Methods: Only randomized controlled trials evaluating internet-based self-help interventions for individuals with IBS were included. A literature search was conducted across PubMed, Embase, Web of Science, CINAHL Complete, PsycINFO, the Cochrane Library, and 4 Chinese databases on June 25, 2025, with an updated search on March 9, 2026. Risk of bias was assessed using the Cochrane Risk of Bias 2.0 tool. Meta-analyses were performed with the Hartung-Knapp-Sidik-Jonkman-adjusted random-effects model. Effect sizes were reported as standardized mean differences (SMDs) with 95% CIs, and evidence certainty was evaluated using GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria. Results: A total of 17 randomized controlled trials from 7 countries were included, involving 2289 participants (predominantly female). Compared with control groups, internet-based self-help interventions were associated with a statistically significant improvement in IBS symptom severity (SMD -0.52, 95% CI -0.78 to -0.26, 95% prediction interval [PI] -1.46 to 0.42), quality of life (SMD 0.57, 95% CI 0.23 to 0.90, 95% PI -0.41 to 1.54), visceral sensitivity (SMD -0.55, 95% CI -0.89 to -0.21, 95% PI -1.43 to 0.33), and depressive symptoms (SMD -0.14, 95% CI -0.27 to -0.01, 95% PI -0.27 to -0.01). However, no statistically significant improvement was observed in anxiety symptoms (SMD -0.03, 95% CI -0.34 to 0.27, 95% PI -0.78 to 0.71). The certainty of evidence was rated as moderate to very low for all outcomes. Conclusions: This review synthesizes the latest evidence on internet-based self-help interventions for individuals with IBS disease-specific and comorbid psychological symptoms. It stands out by encompassing a diverse range of such interventions and incorporating visceral sensitivity as a key outcome. In doing so, it establishes a more comprehensive multi-outcome evidence base for IBS digital interventions, advancing the field by clarifying the potential of these interventions as viable alternatives to conventional treatments. For real-world practice, these findings can inform targeted strategies for primary care and telemedicine platforms, especially in resource-limited regions. However, this review is limited by moderate bias risk, high heterogeneity, and moderate to very low GRADE evidence certainty. A wide 95% PI suggests that effect variability is linked to contextual and population factors, so findings should be interpreted cautiously. Future research should prioritize technical support, patients' digital health literacy, and standardized intervention protocols to further validate clinical utility.