Requester: Gowtham Rao
Background and problem statement: A person’s care journey over time is represented in the visit_occurrence table of the OMOP common data model. Visit_occurrence table represents this journey as span’s of time a person continuously receives medical services from one or more providers at a care_site in a given setting within a health care system. The unit of representation in visit_occurrence is thus a unique combination of person + care_site + continuous care time-span. One visit may involve multiple providers, in which case the ETL must specify how a single provider id is selected or leave the provider_id field null. One visit may involve multiple Care Sites, in which case the ETL must specify how a single care_site id is selected or leave the care_site_id field null.
The standard visit concepts Inpatient Visit, Outpatient Visit, Emergency Room Visit, Long Term Care Visit and combined ER and Inpatient Visit - do not meet the use cases of many in the community. Many in the community have called these lower level granularity as ‘micro visits’, ‘encounters’ etc. and currently there is a desire to capture that information in OMOP CDM to meet those needs.
Many source data, capture data with more granularity than as defined by visit_occurrence table. For example source data may capture encounters/micro-visits/services etc. These may be viewed as arbitrary number of optional micro-visits nested within a main visit, where the actual care delivery happens. Each of these arbitrary number of nested micro-visits may have different start_datetimes, end_datetimes, visit_concept_id, visit_type_concept_id, provider_id, care_site_id, admitting_source_concept_id, discharge_to_concept_id, preceding_visit_occurrence_id, etc. within its own nest. Within each nest sequential relationships between Visits within the nests maybe represented through chaining them in the preceding_visit_occurrence_id.