Effects of participatory organizational interventions on mental health and work performance: A systematic review and meta-analysis

OBJECTIVES: Participatory organizational interventions (POIs) may improve workers' mental health and work performance, but evidence from systematic reviews and meta-analyses of cluster-randomized controlled trials (cRCTs) remains limited: The meta-analysis has not been updated since 2015; a previous study focused on healthcare workers; and potential outcomes have not been adequately examined. This systematic review and meta-analysis aimed to investigate the effects of POIs on mental health and work performance among workers. METHODS: The current study searched PubMed, EMBASE, PsycINFO, PsycARTICLES, and Japan Medical Abstracts Society for papers published by November 11, 2022. Eligible studies were cRCTs assessing the effects of POIs on mental health or work performance. The risks of bias were evaluated by using the Cochrane risk-of-bias tool for cRCTs and performed meta-analysis using a random effects model. RESULTS: Fourteen cRCTs were included in the systematic review, and eight cRCTs in the meta-analysis. The meta-analysis showed non-significant beneficial effect on mental health conditions [the standardized mean differences (SMD) = -0.04, 95%CI; -0.10 to 0.03], positive mental health (SMD = -0.004, 95%CI; -0.077 to 0.068), and work performance (SMD = 0.01, 95%CI; -0.10 to 0.13). CONCLUSION: This study did not confirm that POIs had a statistically significant effect on mental health or work performance. However, several studies that reported favorable results tended to emphasize active and structured participation, alignment with workers' needs, and attention to organizational context. Further research is needed to identify the conditions under which the interventions are effective. Trial registration: The study protocol was registered at the UMIN registry (registration number: UMIN000049453).