Abstract Background The use of health systems data (HSD) such as patient records and prescriptions is expanding within clinical trials to improve efficiency, reduce participant burden, and enhance real‑world relevance. However, challenges remain around governance, data quality, transparency and public trust, echoed through discussions in this project. While Patient and Public Involvement and Engagement is increasingly embedded in trial design, involvement in methodological and data‑focused areas remains limited. Ensuring that HSD trial training for researchers and public reflects public perspectives is therefore important. Methods This work was conducted within HDR UK’s Transforming Data for Trials programme. A Participatory Health Research (PHR) approach was used to develop training resources for the HDR UK Futures online learning platform. A UK‑wide Public Advisory Group (PAG) was recruited through national involvement networks. Engagement took place through virtual full-PAG and small-working‑group meetings. PAG members were involved in identifying priorities, shaping content, reviewing materials and recording videos. Two case studies illustrate different approaches to involvement: co‑production throughout development of a public‑facing module and consultative input to a researcher‑focused module. Results The PAG comprised 25 members with diverse geographical and experiential backgrounds. Case Study 1: members helped develop eight short videos for public partners. They influenced topic selection, tone, language and accessibility of scripts; six members also participated in filming. Their input led to clearer explanations of topics including data governance, consent and trust, with content presented in plain English and modular formats. Case Study 2: PAG members provided feedback on a technical training module on Data Utility Comparison Studies which compare the usefulness of different data sources. Their feedback highlighted concerns about data accuracy, transparency and potential equity implications, prompting refinements to the framing and examples used within the module. Discussion Co‑production supported the development of accessible resources for public research partners, while consultative input helped ensure researcher‑focused training addressed issues relevant to public trust and accountability. These approaches demonstrate how public perspectives can strengthen training related to HSD trial methodology. Conclusion Embedding public perspectives in HSD training development could enhance relevance, accessibility and trust. This work provides a practical model for involving public contributors in methodological training within trials.
Lugg‐Widger et al. (Mon,) studied this question.