What makes a good research invitation for patient and public participants in core outcome set studies: a UK-based consensus meeting to develop guidance.

BACKGROUND: It is crucial that the outcomes used in clinical effectiveness studies are relevant to patients. This relevance can be assured by patients participating with other key stakeholders in core outcome set (COS) studies, yet recruiting patients to such studies can be challenging. OBJECTIVES: As no guidance currently exists to help COS developers create good COS invitations for patients, which are usually the first documents patients see when invited to participate in COS studies, the Good Research Invitation Study aimed to produce such guidance. DESIGN: Consensus meeting to agree on guidance for COS developers designing research invitations. SETTING AND PARTICIPANTS: Informed by findings from our previous qualitative study of patient and public opinions on COS study invitations, our team, which included a patient research partner, produced an initial set of candidate recommendations. An online consensus meeting was organised in the UK with 13 participants including patient research partners with and without COS study experience, COS developers, a representative from an ethics committee and experts in diversity, marketing and science communication. Through a process of discussion and voting, the initial set of recommendations was refined. RESULTS: From the initial 35 recommendations, consensus meeting participants agreed a final set of 22 recommendations. Some initial recommendations were removed as they were beyond the scope, while others were merged. The finalised recommendations focused on producing and user testing invitations, reaching the audience, engaging potential COS participants and considering what they might find appealing or off-putting, explaining and creating interest in the study, keeping the invitation simple and understandable, considering the amount of information to include and how to present it, alongside ensuring accessibility. Discussion during the meeting highlighted the importance of improving the accessibility of all participant-facing resources in COS studies, not just the invitations. CONCLUSION: Through consensus, a set of recommendations has been agreed on for use by COS developers to enhance study invitations for patients. Further testing and refinement of the recommendations will improve their utility.