Abstract
BACKGROUND: Despite growing calls for patient and public involvement (PPI) to improve research relevance and inclusivity, it is still too often implemented in a tokenistic way. Health inequalities persist, and vulnerable populations, such as people with chronic conditions and/or limited health literacy (LHL), remain underrepresented as active participants in research. Factors contributing to this underrepresentation include complex research language, unfamiliar settings, and social stigma. To bridge the gap, this study aims to offer practical lessons that provide researchers and policymakers with concrete strategies for creating inclusive and effective research collaboration processes. METHODS: A participatory action research approach was used, guided by the first three stages of the Participatory Research to Action (PR2A) framework: readiness, discover, and define. Data were collected across five group sessions with ten individuals with type 2 diabetes and various health literacy levels. The analysis focused on process-related data to explore recruitment, facilitation strategies, and participatory experiences. RESULTS: Effective recruitment relied on a multifaceted community outreach approach, combining online and offline channels, which improved group diversity. Clarifying expectations at the outset and balancing structure and flexibility supported meaningful contributions, and allowed sessions to be adapted to individual needs. This approach fostered factors central to motivation and group cohesion, including a collective purpose and mutual respect, while recognising the varied experiences of managing diabetes. Equitable engagement between citizen researchers and PPI facilitators was essential to valuing diverse perspectives and maintaining shared responsibility. Creative co-creation strategies, including sketching and small-group exercises, proved more effective in promoting accessible, inclusive engagement than text-based or plenary-only methods. CONCLUSIONS: The study demonstrates that recruiting and engaging citizens with type 2 diabetes and various health literacy levels as citizen researchers is feasible when conditions such as equitable partnership and engagement, clear expectations, and flexible structures are met. Creative co-creation strategies further support accessible and meaningful participation. These insights provide practical guidance for researchers seeking to implement inclusive PPI, contribute to reducing health inequalities, and inform the next stages of the PR2A framework for advancing participatory health research. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40900-026-00873-w.