Person

Epic equivalent: Patient header / registration demographics

The person table is the center of the OMOP universe — one row per patient. In Epic, demographic details can be split across registration modules, updated with each encounter, and duplicated across systems. In OMOP, all of that consolidates into a single record per individual.

Every other clinical table (condition_occurrence, drug_exposure, measurement, etc.) links back to person_id. This is always your starting point.

Epic-to-OMOP Field Mapping

Field reference (click to expand)

OMOP Field	Epic Equivalent	What It Captures
person_id	MRN / Enterprise ID	Unique patient identifier (re-keyed for privacy)
gender_concept_id	Sex at birth / Gender	Standardized concept — "Male", "Female", etc. May differ from gender_source_value
year_of_birth, month_of_birth, day_of_birth	Date of birth	Split fields to support date shifting for de-identification
race_concept_id	Race (registration)	Standardized race value mapped from source
ethnicity_concept_id	Ethnicity (registration)	Standardized ethnicity value mapped from source
location_id	Home address / ZIP	Foreign key to location table (often de-identified)
provider_id	PCP / Managing physician	Primary provider if available; may be null
care_site_id	Primary facility / department	Main care site attribution
*_source_value fields	Raw EHR text	Original values from the source system (e.g., "M", "Hispanic or Latino")

What to Watch For

Common pitfalls

Snapshot, not history

This table captures the current state. If a patient's address, race, or gender was updated over time, only the latest value is here. For longitudinal demographics, check the observation table.

Birth dates may be shifted

De-identified datasets may truncate or shift dates of birth. Don't assume full precision.

Use concept_id, not source_value

Always use gender_concept_id, race_concept_id, etc. for analysis. The *_source_value fields contain raw EHR text that varies across source systems.

Research Patterns

Question	Tables Involved
Proportion of female African American patients in the database	person.race_concept_id + person.gender_concept_id
Average age at death	person.year_of_birth + death
Statin prescribing disparities across racial groups	person.race_concept_id + drug_exposure
Pediatric patients seen for asthma in the past year	person.year_of_birth + condition_occurrence
Patient characteristics at a specific care site	person.care_site_id + visit_occurrence