Understanding the natural history of rare bone and mineral conditions is essential to improve clinical practice and support the development of new diagnostics and therapies. Patient participation and long-term engagement are key challenges for rare disease registries. Incorporating the perspectives and priorities of patients is essential to ensure that registries collect meaningful information and address outcomes that are relevant to the patient community.

To identify the priorities, expectations, and preferences of patients and their families regarding the content, functionality, and use of a European registry for rare bone and mineral conditions.

The European Reference Network on Rare Bone Diseases (ERN BOND) and European patient advocacy groups developed and conducted a multinational survey using an iterative consensus process. The survey explored preferred registry content, data collection approaches, and functionalities. Responses were collected from individuals affected by rare bone and mineral conditions, including adults, children, parents, guardians, and carers, and were analysed using descriptive statistics and multivariate regression.

A total of 493 eligible responses were collected from 22 rare bone and mineral conditions, including 378 adults, 15 children, and 100 parents, guardians, or carers. Osteogenesis imperfecta represented 53.4% of responses. Information related to improving treatment and medical services was considered most important, while psychosocial aspects such as anxiety and social participation received lower priority scores. Respondents preferred data entry by healthcare professionals; however, the survey showed that relying only on specialist centre visits may result in missing a substantial proportion of individuals living with rare conditions.

This survey identified key components that should be included in a European registry for rare bone and mineral conditions. The findings highlight the importance of combining healthcare professional and patient-reported data collection approaches to obtain comprehensive and representative natural history data.

Patients and families provide essential insights into the outcomes that matter most in rare bone and mineral conditions. The results of this survey have informed the development of patient-centred registry approaches within ERN BOND and EuRR-Bone, supporting the collection of meaningful data to improve research, clinical care, and future therapies.