Co-Designing Accessible Trial Information: Lessons from Designing an Inclusive Patient Information Leaflet in the RaCeR2 Study

Background: Informed consent is fundamental to ethical research, yet participant information leaflets (PILs) are often technical and difficult to understand. Although the importance of accessible study materials is widely recognised, practical guidance on how to achieve remains limited. For RaCeR 2, a randomised controlled trial evaluating different approaches to rehabilitation after shoulder rotator cuff repair, the baseline PIL was developed using Health Research Authority guidance. Early PPI consultation identified major concerns including dense formatting, overly complex language, and an unwelcoming tone, indicating the need for substantial redesign to support informed participation. Description of Patient and Public Involvement Activity: A diverse PPI group (n=5) supported the development of an accessible PIL. Contributors varied in age, gender identity, ethnicity, preferred language, employment status, disability, and experience of shoulder surgery. Engagement methods were tailored to participant needs and included online discussions, written feedback, and in-person “think-aloud” sessions. Given the depth of insight provided during initial PPI consultation, we adopted an iterative, user-centred approach drawing on co-design principles to enable contributors to directly influence the content, structure, and presentation of the PIL. Outcome of the Patient and Public Involvement Activity: Contributors identified challenges with the original materials, including confusing layout, inaccessible formatting, technical terminology, and a tone that did not feel supportive. Through iterative cycles of review and refinement guided by co-design principles, the leaflet was substantially redesigned to include clearer headings, formatting aligned with British Dyslexia Association guidance, bullet-pointed and tiered information, simplified explanations of data protection, and a more conversational tone. Accessibility testing confirmed compatibility with freely available online screen-reading software. During the subsequent regulatory review, inconsistencies between legal requirements and participant preferences highlighted tensions that may limit the accessibility of study materials. Conclusions: This commentary provides a pragmatic example of integrating co-design principles within PPI to create a more accessible PIL. Early engagement, flexible methods, iterative feedback, and testing with screen reading software were central to the process. Our experience also highlights the need for continued dialogue between researchers and regulators to ensure that participant-facing materials meet ethical and legal requirements while remaining understandable to all potential participants.