OMOP EHDEN project: CRN maps its core variables to OMOP CDM

The OMOP data model is well suited to represent registry data. The Cancer Registry of Norway is implementing OMOP-CDM by expanding the necessary infrastructure and directory registry data as part of the "OMOP EHDEN" project.

Background

EHDEN (European Health Data Evidence Network) is an EU project funded by the Innovative Medicines Initiative (IMI), a European public-private partnership. EHDEN works with data partners in the EU, with the goal of harmonizing source data locally into a common data model in a federated network. The computer model used is OMOP-CDM (OMOP-The Observational Medical Outcomes Partnership) and is being developed by the OHDSI community. EHDEN provides support to Data Partners to assist them in "certifying" their source data to the OMOP model.

The OMOP data model is well suited to represent registry data. In addition, there is a common format (terminology, vocabulary and coding scheme) to unify data in the best possible way.

The Cancer Registry of Norway implements OMOP-CDM by developing the necessary infrastructure and directory registry data as part of the "OMOP EHDEN" project. To begin with, it is the KRG's core variables (demographics, diagnosis, primary care, and vital status) that should be mapped to OMOP concepts. This involves mapping data from around 1.3 million patients.

Mapping, or mapping as it can also be termed, involves finding categorizing data from the KRG into specific variables in the OMOP data model. In principle, this is a resource-intensive process, but once the core variables are in place, it will be easier to expand the mapping to the quality registries for specific types of cancer.

The use of the OMOP-CDM will increase the KRG's comformity with the FAIR principles.

The FAIR principles state that data should be be findable, accessible, interoperable and reusable. By adopting such a common data model, the KRG contributes to data in the registry being searchable through international networks for research, accessible via federated analyses, interoperable through a common data model, and available for reuse from previously run standardized analyses. This is taken care of, among other things, because individual data constantly remains locally stored all the time.

Work in progress

So far, the "OMOP EHDEN" project has resulted in an ongoing expansion of the structural infrastructure at the KRG, as well as the completion of the mapping for the core variables. This has been done in collaboration with edenceHealth, which is a certified by EHDEN to assist in mapping source data to OMOP-CDM.

Several projects that will expand mapping to include variables from the quality registers are being planned. Overview and information about ongoing OMOP projects can be found here.