Objectives Medical device registries in Europe report limited information about their structure and methodological characteristics. This hinders their utility for evaluation of medical device safety and performance under the Medical Device Regulation. This study aimed to define a minimum checklist of items necessary for regulators to assess the quality of evidence produced using registry data for the evaluation of medical device safety and performance. Design A three-round Delphi panel. Setting A task within the Coordinating Research and Evidence for Medical Devices project. Participants 101 experts in the medical device community (healthcare professionals, methodologists, registry experts, regulators, and assessors from notified bodies) were invited. Interventions Based on a literature review and expert advice, 27 items relating to the quality of registry data and the analysis of medical device safety and performance were selected. In round 1, participants selected which items were required for a minimum checklist. They could also propose new items. Items selected by ≥70% of participants indicated consensus. Remaining items were discussed in round 2, resulting in a final checklist that was ranked by participants for importance (round 3). Main outcome measures Consensus of items to be included in the minimum checklist. Results 51 experts participated in round 1, achieving consensus on 18 (67%) items and suggesting 12 items. After discussion in round 2, 5 additional items were selected, resulting in a final set of 15 data quality items and 8 data analysis items. The most important items were ‘completeness of procedures’ (data quality) and ‘definition of outcome analyzed’” (quality of analysis). Conclusions Reporting all items from the minimum checklist will facilitate judgment of the utility of registry data to evaluate medical devices during post-market surveillance.

In the European Union (EU) the delivery of health services is a national responsibility but there are concerted actions between member states to protect public health. Approval of pharmaceutical products is the responsibility of the European Medicines Agency, whereas authorizing the placing on the market of medical devices is decentralized to independent 'conformity assessment' organizations called notified bodies. The first legal basis for an EU system of evaluating medical devices and approving their market access was the medical device directives, from the 1990s. Uncertainties about clinical evidence requirements, among other reasons, led to the EU Medical Device Regulation (2017/745) that has applied since May 2021. It provides general principles for clinical investigations but few methodological details-which challenges responsible authorities to set appropriate balances between regulation and innovation, pre- and post-market studies, and clinical trials and real-world evidence. Scientific experts should advise on methods and standards for assessing and approving new high-risk devices, and safety, efficacy, and transparency of evidence should be paramount. The European Commission recently awarded a Horizon 2020 grant to a consortium led by the European Society of Cardiology and the European Federation of National Associations of Orthopaedics and Traumatology, that will review methodologies of clinical investigations, advise on study designs, and develop recommendations for aggregating clinical data from registries and other real-world sources. The CORE-MD project (Coordinating Research and Evidence for Medical Devices) will run until March 2024; here we describe how it may contribute to the development of regulatory science in Europe.