Informing patients about the use of their healthcare systems data in RCTs: a cohort analysis of information leaflets

Abstract Background Patient Information Leaflets (PILs) provide potential participants with the information needed to make an informed decision about joining a randomised controlled trial (RCT). The growing use of healthcare systems data (HSD) adds complexity to documents already under pressure to remain concise. While regulatory requirements exist for transparency about data use, no specific guidance prescribes the level of detail or wording required to describe HSD in PILs. This study examined how PILs from NIHR-funded RCTs communicate HSD use to potential participants. Methods A document analysis was conducted using a cohort of RCTs. Eligibility was determined by NIHR-HTA funding, active trial status in 2022, and planned use of HSD, resulting in 51 eligible RCTs. PILs were obtained through online searches and direct contact with trial teams. Data were extracted using a form based on HRA data protection disclosure requirements. Questions examined data access, linkage, confidentiality and regulatory compliance. PILs were assessed against trial protocols to evaluate completeness of HSD source disclosure. A three-category scale (Vague, Clear, Detailed) captured variation in level of detail. Informed consent forms (ICFs) were reviewed where available. Results PILs were obtained for 43 of the 51 trials (84%). 33 (77%) mentioned at least one HSD source, but of these only 22 (67%) mentioned all sources planned in the protocol. Only 7 (16%) PILs described what specific data would be accessed from HSD. Three ICFs requested consent for HSD use not previously explained in the PIL, raising concerns about informed consent adequacy. HSD detail varied across PILs, from vague references of medical records to detailed descriptions of data linkage and access procedures. Most PILs were in a paper format, referencing additional websites through links. Seven (16%) were presented using a multimedia format, allowing for dynamic explanations of the trial. Conclusion Transparency about data use has been identified as a priority for patients, yet the level of detail provided about HSD is often insufficient to support informed decision-making. There is an absence of guidance for HSD-specific PIL content. ICH E6(R3) requires consent to be based on a process that ensures participants are well informed, while strengthening the governance of external data sources. However, the gap in knowledge of what participants should be told remains unresolved and addressing it would support both trialists and patients.