Mental health is fundamental to living a fulfilling and productive life, yet mental ill-health significantly affects a large part of the population in OECD countries. Depression and anxiety are the most prevalent conditions and have a large burden on population health, well-being and the economy at large – through increased demand for health and social services and reduced workforce productivity. Mild-to-moderate depressive symptoms, affecting one in five adults across OECD and EU27 countries, are of particular concern as they often go unrecognised and untreated, increasing the risk of progression to more severe conditions and contributing to raising overall societal costs.
This report provides OECD and EU27 countries with the means to identify, assess and transfer promising and best practice interventions aimed at promoting good mental health and preventing the deterioration of mental ill-health. It builds on the OECD’s work on assessing Best Practices in public health. Interventions identified in this report are aligned with prevention priorities outlined in the OECD Benchmark for mental health performance, and have been proposed by OECD Member countries or identified through the European Union Best Practices portal. All interventions are assessed against validated best practice criteria from the OECD Guidebook on Best Practices in Public Health. Criteria include effectiveness, efficiency, equity, the quality of the evidence‑base, and the extent of coverage, as well as an assessment of the intervention’s potential to be transferred to another country.
This report presents 11 promising and best practice interventions that promote mental well-being and prevent symptom escalation. These interventions range from school-based resilience programmes and suicide prevention initiatives, to mental health literacy training for front-line professionals, and enhanced access to mental health care and psychological support services (e.g. such as free consultations with mental health professionals, youth walk-in centres, and online tools).
The report shows that these interventions can reduce symptom severity and duration by up to 87%, strengthen protective factors and mental resilience, and improve school attendance and reduce work absenteeism, with improvements ranging from 50% to 61%. OECD simulations also demonstrate that the studied interventions are cost-effective, generating measurable health and labour market savings while remaining within reach for many health systems. Finally, the report identifies common success factors and challenges related to evidence base, programme evaluation, and scale‑up. It also distils key lessons for policymakers on how to improve access to mental health care and support, strengthen evidence base, and scale up effective mental health interventions.