Abstract
Sleep disturbances and mental health issues represent escalating global health challenges, exacerbated by the COVID-19 pandemic and increased digital media consumption. Digital mindfulness-based interventions (DMBIs) have emerged as a scalable and accessible alternative, but no prior meta-analysis has rigorously isolated the effects of standalone DMBIs on sleep and mental health. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) from MEDLINE, Embase, PsycINFO, Web of Science, and the Cochrane Library. Eighteen eligible RCTs were identified, involving a total of 4870 participants for sleep outcomes and 4489 participants for mental health outcomes. Standalone DMBIs significantly improved sleep health with a moderate effect size (Hedges' g = 0.38, p < 0.001; very low-certainty evidence) and mental health with a moderate effect size (Hedges' g = 0.33, p < 0.01; very low-certainty evidence). Sensitivity analyses confirmed the robustness of the findings, and meta-regression demonstrated a dose-response relationship between intervention dose and outcomes. Nevertheless, high heterogeneity and publication bias reduced the certainty of evidence to very low levels. Our findings support the potential of standalone DMBIs as a scalable and cost-effective approach to improve sleep and mental health across diverse adult populations. However, further high-quality research is essential to improve evidence certainty, address adherence challenges, and optimize intervention strategies based on delivery format and population characteristics.