Conflict of interest

GR reports receiving consultancy fees from Astellas (board on Roxadustat, 2019–2021, 2023), GlaxoSmithKline (he serves on the scientific board for Daprodustat in 2022 and 2023), Vifor (board on Difelikefalin, 2021–2023). He reports research funding for scientific presentations from Amgen, Astellas, Baxter, Hemotech, Gambro Hospal, Nipro, Physidia, and Theradial. He also reports receiving honoraria from Amgen, Astellas, GlaxoSmithKline, Roche, Sanofi, and Vifor; and is on the speakers’ bureau for Astellas and Baxter. GR is employed as a nephrologist by the Société d’Exercice Libéral à Responsabilité Limitée (SELARL) (a limited liability company for non-commercial services) de Néphrologie et de Dialyse des Drs Rostoker et Associés, and he is the executive managing officer of the SELARL. SR is a statistician and is employed by the company StatEthic in Levallois-Perret, which she founded. MM is employed as a nurse coordinator in the dialysis center by the private hospital Claude Galien in Quincy-sous-Sénart, HC is employed as an Infection Prevention and Control Registered Nurse by the Claude Galien private hospital in Quincy-sous-Sénart. GB is a collaborator of the SELARL de Néphrologie et de Dialyse des Drs Rostoker et Associés at the Claude Galien private hospital in Quincy-sous-Sénart. MG and CL are employed by the SELARL de Néphrologie et de Dialyse des Drs Rostoker et Associés at the Claude Galien private hospital in Quincy-sous-Sénart. LG is a PhD in Microbiology/Immunology, he is the Global Head of Vaccine Sciences at IQVIA Laboratories in Laval, Canada. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; nor in the decision to publish the results.

Ethical approval

This retrospective observational study was conducted in accordance with French law and did not require approval by an ethics committee. It was conducted in accordance with the Declaration of Helsinki. The study protocol follows the MR-004 reference methodology defined by the Commission Nationale de l’Informatique et des Libertés (CNIL), the French authority for data privacy protection. This study received approval from the scientific committee of the Ramsay Health Cooperation Group for Education and Research (GCS Ramsay Santé, No. COS-RGDS-2021-06-075) and was registered on the public health data hub (registration number F20220207122956).

Informed consent to participate

All participants received information about the study and gave informed oral consent. All data were analyzed unless participants refused to take part in the study.