Comprehensive Resource Guide for Clinical Researchers Utilizing the OMOP Common Data Model

The Observational Health Data Sciences and Informatics (OHDSI) initiative and its OMOP Common Data Model (CDM) have revolutionized collaborative clinical research by standardizing heterogeneous healthcare data into a unified framework. This report synthesizes critical resources—including tools, publications, training materials, and community platforms—to empower researchers navigating OMOP-based studies.

Foundational Resources for OMOP CDM Implementation

Standardized Data Model Documentation

The OMOP CDM specification, maintained by the OHDSI community, defines the structure, conventions, and vocabulary requirements for transforming raw healthcare data into the OMOP format. The official GitHub repository provides Data Definition Language (DDL) scripts for creating OMOP-compliant tables across database platforms like PostgreSQL, RedShift, and SQL Server. The OHDSI website further elaborates on the model’s design philosophy, emphasizing its role in enabling reproducible analytics across disparate datasets.

OHDSI GitHub: https://github.com/OHDSI/CommonDataModel
OMOP Introduction: https://health.ucdavis.edu/data/omop.html

Vocabulary Harmonization Tools

The OHDSI Standardized Vocabularies map diverse coding systems (e.g., SNOMED-CT, ICD-10, RxNorm) to OMOP concepts, ensuring semantic interoperability. Researchers access these vocabularies via the Athena portal, which supports concept browsing, mapping validation, and download. For genomic data integration, the KOIOS tool harmonizes variant call formats (VCFs) with OMOP genomic concepts, automating HGVSg identifier generation and concept ID assignment.

Athena Website: https://athena.ohdsi.org/
KOIOS: https://github.com/OHDSI/Koios

Analytical Tools and Software Ecosystem

Cohort Development and Patient-Level Prediction

ATLAS, OHDSI’s flagship web application, enables cohort definition through intuitive concept searches and temporal criteria. Its Patient-Level Prediction (PLP) module integrates machine learning models for risk stratification, leveraging R packages like PatientLevelPrediction and DeepPatientLevelPrediction. Comparative studies validate ATLAS’s feasibility against custom R workflows, particularly for logistic regression and tree-based models. For advanced users, the Gaia toolchain incorporates geospatial determinants of health into OMOP analyses via gaiaDB (geospatial staging database) and gaiaCore (R package).

ATLAS Website: https://github.com/OHDSI/Atlas
Gaia: https://github.com/OHDSI/GIS

Data Quality Assessment

The Data Quality Dashboard (DQD) evaluates OMOP datasets against 3,300+ predefined checks, categorizing issues using the Kahn Framework (completeness, plausibility, conformance). Complementing this, CohortDiagnostics identifies inconsistencies in cohort definitions across institutions, critical for multicenter studies. A 2025 comparative analysis of Johns Hopkins and Washington University datasets demonstrated how these tools uncover variability in measurement vocabularies and demographic completeness.

Data Quality Dashboard: https://github.com/OHDSI/DataQualityDashboard
Cohort Diagnostics: https://github.com/OHDSI

Training and Community Support

Educational Platforms

The OHDSI Symposium annually features workshops on OMOP CDM ETL processes, ATLAS analytics, and predictive modeling. Recordings and slides are archived on the OHDSI YouTube channel. Institutional training programs, like UF Health’s ATLAS Tutorials , provide step-by-step guides for cohort creation and vocabulary searches. For self-paced learning, The Book of OHDSI offers chapters on CDM design, standardized analytics, and ethical considerations.

Book of OHDSI: https://ohdsi.github.io/TheBookOfOhdsi/
EHDEN Academy: https://academy.ehden.eu/course/view.php?id=4
OHDSI Youtube Channel: https://www.youtube.com/@OHDSI
StanfordSTARR: https://www.youtube.com/@stanfordstarr8476
UF Health's ATLAS Tutorial: https://idr.ufhealth.org/research-services/feasibility-cohort-discovery/uf-health-omop-atlas-training-tools/

Collaborative Forums

The OHDSI Forum hosts active discussions on technical challenges, such as medical image data integration and vocabulary mapping ambiguities. Researchers troubleshoot ETL pipelines, share optimization strategies, and propose CDM extensions. The OHDSI GitHub Organization (321+ repositories) fosters open-source collaboration, with repositories like CommonDataModel and FeatureExtraction enabling version-controlled contributions

OHDSI Forum: https://forums.ohdsi.org/t/help-with-omop-cdm-setup-medical-images-extension/20746

Synthetic and Real-World Data Sources

The CMS SynPUF dataset, a synthetic Medicare beneficiary sample, allows method validation without privacy constraints. Institutions like URMC and UC Davis Health provide de-identified OMOP datasets spanning millions of patients, accessible via IRB-approved requests. The OHDSI Network Research Initiative facilitates federated analyses across 20+ global sites, supporting studies on drug safety, COVID-19 outcomes, and health equity.

CMS SynPUF: https://health.ucdavis.edu/data/omop.html
OHDSI Network Research Initiative: https://www.ohdsi.org/network-research-studies/