The diverse nature of the heterogeneous etiological and clinical spectrum of the MetabERN disease panel necessitates the limitation of data collection to a minimal set of common data elements and the usage of controlled and standardized vocabularies for the description of the clinical phenotype and treatment strategies. The U-IMD registry will collect data using four modules:
Module 1: Common Data Elements
The registry contains a module of common data elements that is uniform across all diseases. U-IMD will use the set of common data elements developed specifically for rare disease registration by the European Commission's Joint Research Centre (DG JRC). The usage of these common data elements is recommended as a constitutive element for all rare disease registries in Europe. It is a necessary prerequisite for working with the EU Rare Diseases Registries Platform (EU RD Platform), a set of tools developed by the DG JRC that aims to cope with the enormous fragmentation of data collected by rare disease registries throughout Europe.
Module 2: Clinical and biochemical phenotype
The registry contains a module for clinical phenotyping that is uniform across all diseases. This module will use the Human Phenotype Ontology as an established, controlled and standardized vocabulary for phenotyping clinical abnormalities, thus ensuring interoperability with other registries using the same vocabulary for phenotyping and comparability of phenotypes across all diseases in the registry. In addition to HPO, results of standard IQ tests will be included.
Module 3: Patient perspective
The registry contains a module for adequately capturing the patient perspective that is uniform across all diseases. PedsQL and WHOQOL-BREF questionnaires can be filled in by the patients directly and have been translated and validated in multiple languages. These tools have already been successfully used in the E-IMD, E-HOD and iNTD registries. If available, disease-specific health-related QoL tools will be also included. To evaluate the impact of patients for caring for children with an IMD, the Parenting Stress Index (PSITM-4) will be included.
Module 4: Treatment
The registry contains module for capturing drug treatment that is uniform across all diseases. This module will use the WHO ATC classification system as an established, controlled and standardized vocabulary. WHO ATC codes drugs with a five-tiered classification system, from the treated organ system down to the respective chemical substance. Off-Label or Orphan drug usage will be recorded.
U-IMD is committed to a lean data model. Nevertheless assessing the state of play regarding rare disease registration is a project task, thus U-IMD will consider the addition of further standardized vocabularies like the small molecule metabolites classification system developed by the Human Metabolome Database (HMDB) or UniProt for proteins among others.