Weaving a theory of change: mapping the pathway for Peer Support implementation in community mental health services in Brazil through co-produced participatory workshops

Abstract Background Peer Support (PS) has gained increasing recognition as a recovery-oriented practice in mental health services by valuing the experiential knowledge of individuals with lived experience of psychological distress. While PS has been widely implemented in high-income countries, its integration into public mental health systems in low- and middle-income settings remains limited and insufficiently documented. Objective This study aimed to co-produce a Theory of Change (ToC) to support PS implementation in community mental health services in Brazil, identify contextual determinants using the Consolidated Framework for Implementation Research (CFIR), and map implementation strategies informed by the Expert Recommendations for Implementing Change (ERIC). Methods A participatory qualitative pre-implementation study was conducted within the Psychosocial Care Network of Campinas, Brazil. Participatory workshops were held with stakeholders - including individuals with lived, clinical and research experience in mental health - to collaboratively develop a ToC for PS implementation. Data from workshops and field observations were analyzed thematically and organized using CFIR to identify contextual barriers and facilitators. Identified determinants were subsequently linked to implementation strategies using the ERIC taxonomy. Results The participatory process resulted in a ToC that specified key resources, priority implementation strategies, expected outcomes, and underlying assumptions for integrating PS into community mental health services. CFIR-informed analysis identified determinants across multiple domains, including facilitators related to the recognition of lived experience as a legitimate form of knowledge and barriers associated with institutional resistance, resource constraints, and challenges in integrating peer roles into existing service structures. The integration of CFIR and ERIC enabled the identification and prioritization of context-adapted implementation strategies, particularly those focused on workforce training, stakeholder engagement, and strengthening interprofessional collaboration within services. Conclusions Integrating participatory ToC development with implementation science frameworks provided a structured and context-sensitive approach to planning PS implementation in Brazilian community mental health services. The combined use of ToC, CFIR, and ERIC strengthened the alignment between contextual analysis and strategy selection, supporting the development of feasible and locally grounded implementation pathways. This approach contributes to advancing participatory and theory-informed implementation methods for recovery-oriented interventions in complex public health systems.