Evidence Hub

Impacts of digital third-wave interventions for adults on wellbeing and mental health outcomes: A systematic review and meta-analysis of randomized controlled trials

Tom C. Gordon, A. Kemp, Josh Hope-Bell, Darren J. Edwards

PLOS Digital Health, 2026

26,391 participants

Abstract

To synthesise the efficacy of digital third-wave process-based interventions (e.g., ACT, Mindfulness, Compassion) for improving wellbeing and ameliorating mental health symptoms in adults. A prospectively registered systematic review (OSF: 10.17605/OSF.IO/5RMU2) and random-effects meta-analysis of randomised controlled trials (RCTs) was conducted across six databases through January 2026. Certainty of evidence was assessed using the GRADE framework. Interventions (k = 147; N = 26,391) yielded small-to-moderate immediate post-intervention improvements in wellbeing (k = 46, g = 0.36), depression (k = 110, g = 0.44), anxiety (k = 93, g = 0.40), stress (k = 66, g = 0.46), quality of life (k = 32, g = 0.30), and psychological flexibility (k = 51, g = 0.41). Heterogeneity was substantial across most outcomes (I2 > 75%). Benefits were observed across healthy (61 trials; n = 15,770), mental health (41 trials; n = 6,130), and medical samples (46 trials; n = 4,491), with population type not significantly moderating immediate post-intervention effects. Comparator type significantly moderated several analyses, with smaller effects against active than inactive controls. Guidance did not significantly moderate immediate post-intervention effects, although it predicted larger short-term depression effects (QM = 4.17, p = .048). At short-term follow-up, effects remained statistically supported across all outcomes, while only depression, anxiety, and stress remained statistically supported…

How strong is the evidence?

Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid. Reported size: 26,391 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free