Ontology Strategy

This page outlines recommended standard practices for applying ontologies.

Data Class	OMOP Standard	NHS Preferred	Concept_ID	Source_Concept_ID	Comments
Clinically recorded conditions	SNOMED	SNOMED	SNOMED	Any	Use SNOMED
Coding/ Billing Diagnosis	SNOMED	ICD-10	SNOMED	ICD-10	Mapping from ICD-10 to SNOMED will need to be done using OMOP tables. Include the original ICD-10 codes in the source_value field.
Labs	LOINC	SNOMED	LOINC	Any	Most labs and EHRs in the UK are not mapped to a standard ontology. Currently the NHS is still working on its unified test list but this is not yet in Athena.
Drugs	RxNORM	dm+d	dm+d	Any	Most NHS orgs use First Databank (FDB) that have mappings for dm+d. This is often stored within the EHR.
Physiological Observations	LOINC/SNOMED	SNOMED	LOINC/SNOMED	Any	OMOP accepts LOINC and SNOMED as standard terminology. There is a strong preference to use SNOMED here wherever possible.
Procedures		SNOMED/OPCS-4		Any

Handling Exceptions

In rare situations there may not be an appropriate mapping. OMOP reserves concept ids > 2,000,000,000 for custom mappings. However, these should be used rarely. It is much more likely that we can find an appropriate existing representation.