Clinical Data

These are the tables you'll query most. Each captures a different domain of patient-level clinical data — the OMOP equivalent of what you'd find across Clarity's diagnosis, medication, lab, procedure, and encounter tables.

Start with these five

Most research projects use person, visit_occurrence, condition_occurrence, drug_exposure, and measurement. Everything else builds on that foundation.

Core Tables

• Person

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  One row per patient. Demographics, birth date, race, ethnicity. The center of the OMOP universe.

  Person

• Visit Occurrence

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  Encounters — inpatient, outpatient, ER, telehealth. The OMOP equivalent of Epic's encounter table.

  Visit Occurrence

• Visit Detail

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  Sub-encounter segments: ICU stays, department transfers, ADT events within a broader visit.

  Visit Detail

• Condition Occurrence

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  Diagnoses and problems. Maps to encounter diagnoses and problem list entries from Epic.

  Condition Occurrence

• Drug Exposure

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  Medication orders, administrations (MAR), prescriptions, and pharmacy data.

  Drug Exposure

• Measurement

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  Lab results and vital signs — A1c, hemoglobin, blood pressure, creatinine, and more. All in one table.

  Measurement

• Observation

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  The catch-all for clinical facts that don't fit elsewhere: smoking status, social determinants, screening responses, patient-reported outcomes.

  Observation

• Procedure Occurrence

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  Surgeries, imaging orders, vaccinations, interventional procedures. Maps to Epic procedure orders and surgical case records.

  Procedure Occurrence

Additional Clinical Tables

• Death

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  Mortality data from EHR discharge records and state death indices.

  Death

• Device Exposure

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  Medical devices: pacemakers, catheters, implants, glucose monitors. Often sparse in EHR-derived OMOP.

  Device Exposure

• Note / Note NLP

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  Unstructured clinical text (progress notes, discharge summaries, radiology reports) and NLP-extracted entities.

  Note Note NLP

• Specimen

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  Biological samples: blood, tissue, urine. Linked to Winship's OpenSpecimen biobank at Emory.

  Specimen

• Fact Relationship

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  Cross-domain links: connecting a biopsy procedure to its pathology result, or a pregnancy diagnosis to a delivery.

  Fact Relationship

Derived Elements

These tables are computed from the raw clinical tables above — they aggregate events into clinically meaningful periods.

• Condition Era

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  Continuous periods of a diagnosis, aggregated from condition_occurrence using gap logic (default 30-day window).

  Condition Era

• Drug Era / Dose Era

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  Continuous medication exposure periods and consistent-dose periods, derived from drug_exposure.

  Drug Era Dose Era

• Episode / Episode Event

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  Higher-level clinical constructs: treatment regimens, pregnancy episodes, disease courses. Explicitly curated during ETL or by researchers.

  Episode Episode Event