When to Use OMOP
Emory has multiple data platforms. Choosing the right one saves weeks of work. This guide helps you decide when Enterprise OMOP is the right fit — and when you should use Epic Clarity, Caboodle, or the Reporting Workbench instead.
OMOP vs. Epic Resources at a Glance
| Enterprise OMOP | Epic Clarity / Caboodle | Reporting Workbench | |
|---|---|---|---|
| Best for | Multi-source research, standardized analytics, federated studies | Operational reporting, real-time data, full encounter detail | Quick ad-hoc operational reports |
| Data sources | Epic Clarity + Legacy CDW (Cerner) + Tumor Registry + OpenSpecimen | Epic only | Epic only |
| Coding | Standardized (SNOMED, RxNorm, LOINC) | Source codes (ICD-10, CPT, NDC) | Source codes |
| Structure | Patient-centric, cleaned, de-duplicated | Encounter-centric, raw | Pre-built report templates |
| Timeliness | Periodic refresh (lags real-time) | Near real-time | Near real-time |
| Cross-site | Yes — OHDSI network-compatible | No | No |
| Vocabularies | Hierarchies + mappings built in | Manual code lists | Manual code lists |
Use OMOP When...
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Comparative effectiveness research
Comparing treatments, outcomes, or utilization patterns across patient populations using standardized codes and clean data.
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Federated or multi-site studies
Running analyses that need to be portable across OHDSI network sites. OMOP's standard structure means your query works everywhere.
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Linking across data sources
Combining EHR data with tumor registry (Winship) or biospecimen data (OpenSpecimen) in a single, patient-centric model.
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Cohort definitions using standard vocabularies
Using SNOMED hierarchies to capture "all diabetes" without manually listing every ICD-10 code. The vocabulary does the work.
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Health equity and SDoH analyses
Standardized demographics, geographic data, and observation-domain social determinants in a research-ready format.
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You need cleaned data
Non-events (cancelled encounters, missed medications, future procedures) are excluded. What's in OMOP is what actually happened.
Don't Use OMOP When...
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You need real-time or near-real-time data
OMOP refreshes on a periodic cadence. If your study depends on today's data, start with an Epic resource.
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You need the full encounter narrative
OMOP captures what happened to the patient, not everything the provider intended. Cancelled orders, missed medications, and charge-only entries are excluded. Use Clarity for the complete picture.
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Intent-to-treat analysis
If your study is about what care the provider tried to deliver (not what the patient received), Clarity or the CDW is the better source.
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Historical demographic tracking
OMOP's
persontable is a snapshot — it doesn't track address changes, insurance transitions, or prior name/gender over time. -
Operational or billing reports
Charge data, scheduling workflows, and real-time census are Epic's domain. OMOP is built for research, not operations.
What OMOP Actually Is (Under the Hood)
Enterprise OMOP is a structural standardization and semantic harmonization of the data in Epic Clarity and the legacy Clinical Data Warehouse (primarily Cerner). In practice, that means:
- Structural standardization
- All medications land in
drug_exposure, all diagnoses incondition_occurrence, all labs inmeasurement— regardless of which source system they came from. - Semantic harmonization
- NDC codes map to RxNorm. ICD-10 maps to SNOMED. Local lab codes map to LOINC. The vocabulary layer translates source codes into a shared language.
- Cleaning
- Non-events are removed. Records are de-duplicated where applicable. The result is a curated research dataset, not a raw operational dump.
OMOP is not a replacement for Clarity
It's a research-optimized view of the same underlying data. If something looks unexpected in OMOP, the source of truth is always the Epic infrastructure. See our Known Issues page for documented limitations.
Next Steps
Ready to explore the data model? Head to the OMOP Primers landing page for table-by-table guides, or jump straight to the tables you'll use most:
- Person — start here, it's the center of everything
- Visit Occurrence — the encounter equivalent
- Condition Occurrence — diagnoses and problems
- Drug Exposure — medications
- Measurement — labs and vitals