The development of the European Health Data Space (EHDS) places new expectations on how secondary‑use health data should be accessed, combined and analysed. In this context, running a large Findata‑governed project that spans multiple data controllers and modalities offers a concrete view of what this work entails in practice. This presentation shares insights from our contribution to IDERHA, a European public–private partnership integrating heterogeneous health data for regulatory‑grade evidence generation. Using a lung cancer use case, the work required integrating EHR data, CT imaging and related contextual variables from several data holders, offering a concrete view on the current practicalities and challenges.

The talk reflects on our experiences across the life cycle of real-world health data. This includes early-phase data discovery, navigating contractual and governance arrangements, and managing the timelines and dependencies introduced by formal data permit processes. We discuss about to data quality assessment, challenges associated with large-scale datasets, the use of both OMOP-standardised and non-OMOP data formats, and working within secure processing environments.

The goal of this presentation is to offer an experience-based perspective on how complex secondary-use health data projects operate in practice, beyond policy aspirations and technical architectures. By sharing lessons learned, we aim to highlight where current governance models work well and where friction remains. Finally, we reflect on the implications of these experiences for health data and AI research, especially aligned with the EHDS principles.