Are school-based mindfulness interventions effective? A Campbell systematic review and meta-analysis

Article type
Authors
Maynard B1, Solis M2, Miller V3, Brendel K4
1Saint Louis University and Campbell Collaboration
2University of California Riverside
3University of Texas Austin
4Aurora University
Abstract
Background: Mindfulness-based interventions (MBIs) have been gaining widespread support by schools, practitioners and policy makers to address multiple and varied outcomes for youth; however, the strength of the evidence to support such adoption is not clear.
Objectives: The purpose of this review was to examine evidence of MBIs implemented in school settings on academic, behavioural, cognitive and socio-emotional outcomes to inform practice and policy.
Methods: Systematic review and meta-analytic procedures were used to examine effects of school-based MBIs on academic, behavioural, and socio-emotional outcomes for students. A comprehensive and systematic search was undertaken to locate published and unpublished randomised or quasi-experimental studies conducted between 1990 and 2016. Descriptive analysis was conducted to examine and describe characteristics of included studies including risk of bias. Two coders independently screened studies and extracted data from included studies. Effect sizes were calculated using the standard mean difference effect-size statistic, corrected for small sample size bias (Hedges’ g). Meta-analysis, assuming random effects models using inverse variance weights, was used to quantitatively synthesise results across studies.
Results: Thirty-five studies met inclusion criteria for this review. Overall, there was a moderate to high risk of bias across the 35 studies. Meta-analytic findings indicate small, yet statistically significant effects on cognitive outcomes and socio-emotional outcomes and small and non-significant effects on academic outcomes.
Conclusions: The findings largely correspond to what we might expect given the mechanisms by which mindfulness interventions are hypothesised to work (i.e. more directly targeting cognitive and socio-emotional processes). Additionally, we know little about the costs and adverse effects of school-based MBIs—the costs of implementing these programmes may not be justified, and there are some indications that MBIs may have some adverse effects on youth. Given our findings, the evidence from this review urges caution in the enthusiasm for, and widespread adoption of, MBIs in schools.