Learning from real-world conditions to advance green care for mental health equity in the Global North: protocol for a transdisciplinary multi-scalar project.

introductionThere is increasing evidence that green care (from nature-in-everyday life and nature-based health promotion to nature-based therapy) can promote mental health and well-being. However, there is contradictory evidence and few large-scale international studies focused on health inequities. The GreenME project aims to identify ways in which effective green care can be scaled-up to improve adult mental health and well-being equity while contributing to multiple socio-ecological co-benefits across the Global North. METHODS AND ANALYSIS: GreenME's approach is threefold: (i) to diagnose the current status of green care in project consortium countries through a grey literature review and stakeholder interviews, (ii) to increase scientific evidence on the relationship between green care and mental health and well-being equity using modified randomised controlled trials and a population-level socioecological cross-sectional survey study and (iii) to empower green care actors by co-creating a set of tools with consortium countries' participating stakeholders. GreenME will: (a) produce a catalogue of identified successful green care models and best practices; (b) design a robust but adaptable protocol for testing the pathways, effectiveness and cost-effectiveness of nature-based therapies; (c) identify the mental health equity impact of green care and (e) co-create solutions for national and EU-level policies and develop online resources for nature-based therapy providers. GreenME is conceptualised and designed to increase the use of green care and its integration within a multi-scalar green care framework which could ultimately promote just and sustainable healthy communities. ETHICS AND DISSEMINATION: Ethical approval has been obtained individually from each partner/site (UAB CERec 6594, 6851, UAB-CERec180, UAB-CERec178 and CEEAH 7269; UOC CE23-PR29, CE240PR07, CE24-PR59, CE24-PR55; l'Hospital de Mataró CEIm 11/2; CEIm Fundació Sant Joan de Déu PIC-82-25; Alma Mater Stadiorum Universita di Bologna, Proj nos. 0157655, 0075975; ILS, no number 'Survey in Workpackage 2', no number 'Workshops in Workpackage 5'; Swedish Ethics Review Committee, 2024-2810-01, 2025-0195401; University of Kent, CREAG064-04-024; University of Salford Ethics Administration, Ref 0189, 4552; Institute of Psychiatry and Neurology Bioethics Committee, no number; Committees on Ethics and Scientific Research, Res no 32/RKF/2023U). All study results will be disseminated through peer-reviewed publications, scientific conferences and via reports and workshops for stakeholders at the regional (European Union), national and local levels. TRIAL REGISTRATION NUMBER: ISRCTN13105773, ISRCTN71485431, ISRCTN11841855, ISRCTN14970007 and ISRCTN15381820.