Condition Domain
Conditions are records of a Person suggesting the presence of a disease or medical condition stated as a diagnosis, a sign or a symptom, which is either observed by a Provider or reported by the patient. Note that the Condition Domain makes no distinction between a mere observation of a symptom, a fully worked out diagnosis or anything in between.
Condition domain Concepts should be used only in the condition_concept_id fields of the CONDITION_OCCURRENCE and CONDITION_ERA tables, as well as the value_as_concept_id field in the OBSERVATION table (for observations “History of”, “Family history of” etc.).
Structure of Condition Domain
Standard Concepts are taken from the SNOMED vocabulary. All valid (invalid_reason is null) SNOMED Concepts of the Condition Domain are Standard Concepts and can therefore be used in the condition_concept_id in the CONDITION_OCCURRENCE and CONDITION_ERA tables.
SNOMED is a hierarchical vocabulary. Therefore SNOMED concepts can also be used as Class Concepts: descendants of any SNOMED Concept in the CONCEPT_ANCESTOR table can be expected to be a correct semantic match in a query.
MeDRA is used as an additional classification system. The connection between MedDRA and SNOMED is accomplished at the level of MedDRA Preferred Term Concept to the equivalent SNOMED concept. As a result, MedDRA Concepts can also be used to query data, where SNOMED descendants of any MedDRA Concept in the CONCEPT_ANCESTOR table can be expected to be a correct semantic match. However, MedDRA Low Level Term Concepts are not mapped to SNOMED. Also, due to this selective mapping, SNOMED Concepts that are more general than their MedDRA Preferred Term equivalent cannot be retrieved by a CONCEPT_ANCESTOR query.
All Source Vocabularies are mapped to SNOMED Standard Concepts. The mapping is either provided by the vocabulary source (Read, CIEL, MeSH) or developed by the Vocabulary Team.
A number of different sources (UMLS, NHS) were used as input for a mapping between ICD10CM and SNOMED, and then manually curated by the vocabulary team. Note that ICD10 contains predominantly Condition Concepts, but also Procedure, Observation, Device, Measurement or mixed Concepts. Note: Do not use this mapping for ICD10CM (US-Version) Concepts. ICD10 and ICD10CM concepts with the same concept_code may or may not have the same semantic definition.
A number of different sources (UMLS, NHS) were used as input for a mapping between ICD10CM and SNOMED, and then manually curated by the vocabulary team. Note that ICD10CM contains predominantly Condition Concepts, but also Procedure, Observation, Device, Measurement or mixed Concepts. Note: Do not use this mapping for ICD10 (WHO-Version) Concepts. ICD10 and ICD10CM concepts with the same concept_code may or may not have the same semantic definition.
The Read distribution contains a mapping to SNOMED. This mapping is used, and deprecated SNOMED target Concepts are replaced by their valid updates. Note: Many of the Read codes are mapped to SNOMED-UK Concepts if there is no appropriate Concept in SNOMED-Int or if they haven't been de-duplicated yet.
This mapping was curated by the vocabulary team.
The CIEL distribution contains a mapping to SNOMED. This mapping is used, and deprecated SNOMED target Concepts are replaced by their valid updates.
The mapping from MeSH to SNOMED contained in the UMLS distribution was used.
A number of different sources (UMLS, HLI) were used as input for a mapping between ICD9CM and SNOMED, and then manually curated by the vocabulary team. Note that ICD9CM contains predominantly Condition Concepts, but also Procedure, Observation, Device, Measurement or mixed Concepts.
A number of different sources (UMLS, MSSO) were used as input for a mapping between ICD9CM and MedDRA, and then manually curated by the vocabulary team. Note: This mapping is provided for historical reasons and convenience, but does not participate in the hierarchical structure of the Condition Domain.
All relationships provided by SNOMED and MedDRA are loaded, but renamed to follow the relationship_id formatting rules and allow for bi-directional mappings, see SNOMED and MedDRA.