Optimising cohort data in Europe

Issues

Challenges and obstacles

− Affect quality of data if a cohort persists in using the same technology throughout different data collection over the years (e.g. array-based gene expression instead of RNAseq). − Selection of data that are not inferentially equivalent. − Difficulties in the implementation of standardisation process in epidemiological and biological studies. − Use of different standards for the same measure. − Collection of bad quality/incomplete data due to rapid change of standards in relation to technologies. − Heterogeneity in governance for infrastructure. − Centralised data and privacy issues. − Differences in specific tools and approaches for federated platform interfaces. − Confounding variables (contextual, cultural, society, policy-making … ) arising during time could interfere with results of different replicated studies conducted in different years. − Can occur for many reasons (loss of contact, motivation, engagement, death, rejection of consent … ) and can affect seriously the cohort sample size. − Differences in ethical considerations between countries during the design phase (e.g. minimum age or women autonomy for being entitled to sign an informed consent). − Interplay and potential contradiction between national legal frameworks.

Scientific and technological progress

Standardisation and comparability

Sustainability of data infrastructures

Replicability

Lost to follow up

Transnational ELSI

In relation to proper metadata and metadata documentation as pre-requisites for future cohort data re-use and integration, the challenges to overcome are: y y Lack of open documentation and description of metadata. y y The current landscape of existing standards should be mapped. y y Need of consensus on a minimal appropriate level of metadata documentation. y y Determination of standard metadata content. y y Encouragement and incentivising metadata collection. 4. Best practices, solutions and implications for implementation Data access regulations in the cohort access domain are major challenges in most initiatives, especially when sharing data beyond the own cohort. Local regulations and internal access rules of the infrastructures where data is located generate an additional complexity level to the GDPR framework that governs data protection in the European Economic Area (EEA. Overcoming the potential obstacles requires appropriate strategies not only for proper data access, but also for harmonisation and integration of data.