Rare disease registries are essential tools for improving knowledge of rare conditions, supporting clinical research, facilitating clinical trials, and improving patient care. However, the rapid development of registries across Europe has resulted in considerable variation in registry design, governance, data quality, and interoperability. Establishing common recommendations and quality standards is therefore essential to maximise the value of rare disease registries.

To provide recommendations for improving the quality of rare disease registries and to define key requirements for the development, management, and sustainability of high-quality registries supporting research and healthcare activities.

A multidisciplinary expert group, including representatives from rare disease registries, research infrastructures, healthcare professionals, and patient organisations, developed recommendations within the framework of RD-Connect. The recommendations addressed major aspects of registry quality, including governance, data standards, interoperability, infrastructure, documentation, training, and quality assessment.

A comprehensive set of recommendations was developed to support both existing and newly established rare disease registries. Key areas identified included clear governance structures, the use of standardised and interoperable data elements, application of FAIR data principles (Findable, Accessible, Interoperable and Reusable), appropriate documentation, regular quality audits, and continuous improvement processes. These recommendations provide a framework for developing sustainable registries capable of supporting research, healthcare planning, and international collaboration.

The implementation of common quality standards is essential to improve the reliability, comparability, and usefulness of rare disease registries. Applying these recommendations can strengthen registry infrastructure, facilitate data sharing, and support better outcomes for patients with rare diseases.

High-quality registries are fundamental for advancing knowledge and improving care for people living with rare diseases. These recommendations provide an important framework for the development and optimisation of international registries, including registries established within European Reference Networks.