CONDITION_OCCURRENCE

Table Description

This table contains records of Events 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.

User Guide

Conditions are defined by Concepts from the Condition domain, which form a complex hierarchy. As a result, the same Person with the same disease may have multiple Condition records, which belong to the same hierarchical family. Most Condition records are mapped from diagnostic codes, but recorded signs, symptoms and summary descriptions also contribute to this table. Rule out diagnoses should not be recorded in this table, but in reality their negating nature is not always captured in the source data, and other precautions must be taken when when identifying Persons who should suffer from the recorded Condition. Record all conditions as they exist in the source data. Any decisions about diagnosis/phenotype definitions would be done through cohort specifications. These cohorts can be housed in the COHORT table. Conditions span a time interval from start to end, but are typically recorded as single snapshot records with no end date. The reason is twofold: (i) At the time of the recording the duration is not known and later not recorded, and (ii) the Persons typically cease interacting with the healthcare system when they feel better, which leads to incomplete capture of resolved Conditions. The CONDITION_ERA table addresses this issue. Family history and past diagnoses (‘history of’) are not recorded in this table. Instead, they are listed in the OBSERVATION table. Codes written in the process of establishing the diagnosis, such as ‘question of’ of and ‘rule out’, should not represented here. Instead, they should be recorded in the OBSERVATION table, if they are used for analyses. However, this information is not always available.

ETL Conventions

Source codes and source text fields mapped to Standard Concepts of the Condition Domain have to be recorded here.

CDM Field	User Guide	ETL Conventions	Datatype	Required	Primary Key	Foreign Key	FK Table	FK Domain
condition_occurrence_id	The unique key given to a condition record for a person. Refer to the ETL for how duplicate conditions during the same visit were handled.	Each instance of a condition present in the source data should be assigned this unique key. In some cases, a person can have multiple records of the same condition within the same visit. It is valid to keep these duplicates and assign them individual, unique, CONDITION_OCCURRENCE_IDs, though it is up to the ETL how they should be handled.	integer	Yes	Yes	No
person_id	The PERSON_ID of the PERSON for whom the condition is recorded.		integer	Yes	No	Yes	PERSON
condition_concept_id	The CONDITION_CONCEPT_ID field is recommended for primary use in analyses, and must be used for network studies. This is the standard concept mapped from the source value which represents a condition	The CONCEPT_ID that the CONDITION_SOURCE_VALUE maps to. Only records whose source values map to concepts with a domain of “Condition” should go in this table. Accepted Concepts.	integer	Yes	No	Yes	CONCEPT	Condition
condition_start_date	Use this date to determine the start date of the condition	Most often data sources do not have the idea of a start date for a condition. Rather, if a source only has one date associated with a condition record it is acceptable to use that date for both the CONDITION_START_DATE and the CONDITION_END_DATE.	date	Yes	No	No
condition_start_datetime		If a source does not specify datetime the convention is to set the time to midnight (00:00:0000)	datetime	No	No	No
condition_end_date	Use this date to determine the end date of the condition	Most often data sources do not have the idea of a start date for a condition. Rather, if a source only has one date associated with a condition record it is acceptable to use that date for both the CONDITION_START_DATE and the CONDITION_END_DATE.	date	No	No	No
condition_end_datetime		If a source does not specify datetime the convention is to set the time to midnight (00:00:0000)	datetime	No	No	No
condition_type_concept_id	This field can be used to determine the provenance of the Condition record, as in whether the condition was from an EHR system, insurance claim, registry, or other sources.	Choose the CONDITION_TYPE_CONCEPT_ID that best represents the provenance of the record. Accepted Concepts. A more detailed explanation of each Type Concept can be found on the vocabulary wiki.	integer	Yes	No	Yes	CONCEPT	Type Concept
condition_status_concept_id	This concept represents the point during the visit the diagnosis was given (admitting diagnosis, final diagnosis), whether the diagnosis was determined due to laboratory findings, if the diagnosis was exclusionary, or if it was a preliminary diagnosis, among others.	Choose the Concept in the Condition Status domain that best represents the point during the visit when the diagnosis was given. These can include admitting diagnosis, principal diagnosis, and secondary diagnosis. Accepted Concepts.	integer	No	No	Yes	CONCEPT	Condition Status
stop_reason	The Stop Reason indicates why a Condition is no longer valid with respect to the purpose within the source data. Note that a Stop Reason does not necessarily imply that the condition is no longer occurring.	This information is often not populated in source data and it is a valid etl choice to leave it blank if the information does not exist.	varchar(20)	No	No	No
provider_id	The provider associated with condition record, e.g. the provider who made the diagnosis or the provider who recorded the symptom.	The ETL may need to make a choice as to which PROVIDER_ID to put here. Based on what is available this may or may not be different than the provider associated with the overall VISIT_OCCURRENCE record, for example the admitting vs attending physician on an EHR record.	integer	No	No	Yes	PROVIDER
visit_occurrence_id	The visit during which the condition occurred.	Depending on the structure of the source data, this may have to be determined based on dates. If a CONDITION_START_DATE occurs within the start and end date of a Visit it is a valid ETL choice to choose the VISIT_OCCURRENCE_ID from the Visit that subsumes it, even if not explicitly stated in the data. While not required, an attempt should be made to locate the VISIT_OCCURRENCE_ID of the CONDITION_OCCURRENCE record.	integer	No	No	Yes	VISIT_OCCURRENCE
visit_detail_id	The VISIT_DETAIL record during which the condition occurred. For example, if the person was in the ICU at the time of the diagnosis the VISIT_OCCURRENCE record would reflect the overall hospital stay and the VISIT_DETAIL record would reflect the ICU stay during the hospital visit.	Same rules apply as for the VISIT_OCCURRENCE_ID.	integer	No	No	Yes	VISIT_DETAIL
condition_source_value	This field houses the verbatim value from the source data representing the condition that occurred. For example, this could be an ICD10 or Read code.	This code is mapped to a Standard Condition Concept in the Standardized Vocabularies and the original code is stored here for reference.	varchar(50)	No	No	No
condition_source_concept_id	This is the concept representing the condition source value and may not necessarily be standard. This field is discouraged from use in analysis because it is not required to contain Standard Concepts that are used across the OHDSI community, and should only be used when Standard Concepts do not adequately represent the source detail for the Condition necessary for a given analytic use case. Consider using CONDITION_CONCEPT_ID instead to enable standardized analytics that can be consistent across the network.	If the CONDITION_SOURCE_VALUE is coded in the source data using an OMOP supported vocabulary put the concept id representing the source value here.	integer	No	No	Yes	CONCEPT
condition_status_source_value	This field houses the verbatim value from the source data representing the condition status.	This information may be called something different in the source data but the field is meant to contain a value indicating when and how a diagnosis was given to a patient. This source value is mapped to a standard concept which is stored in the CONDITION_STATUS_CONCEPT_ID field.	varchar(50)	No	No	No