OHNLP/omopmcp
OHNLP/omopmcp (OMOP MCP Server) is an open‐source tool that leverages large language models to map clinical terminology to OMOP (Observational Medical Outcomes Partnership) standard concepts. It is designed to facilitate healthcare data standardization and interoperability by automating the otherwise manual and expert‐intensive process of aligning diverse clinical vocabularies (e.g., SNOMED CT, ICD‐10, local codes) to the OHDSI OMOP Common Data Model. The server implements the Model Context Protocol (MCP), allowing AI agents and applications to programmatically request terminology mappings through a well‐defined interface. The tool exposes a set of tools that accept raw clinical terms or codes and return the best‐matching OMOP concept IDs along with confidence scores, concept names, and domain information. It uses configurable LLM backends (such as local models or cloud APIs) to perform semantic matching, which can handle ambiguous, misspelled, or colloquial terms. The system also supports batch processing and caching to improve performance and reduce costs when handling large volumes of data. OMOP MCP Server is built in Python and can be deployed as a containerized service using Docker, or integrated directly into existing Python pipelines via pip. It is designed for healthcare data engineers, clinical informaticians, and researchers who need to build or maintain OMOP‐compliant data warehouses. By providing a programmatic and LLM‐driven approach, it reduces the reliance on manual mapping tools and accelerates the conversion of raw clinical data into a standardised format suitable for observational research, real‐world evidence generation, and cross‐institutional analytics.
- Category
- Developer Tools
- Pricing
- Open Source
Problem solved
Healthcare organizations often store patient data using a variety of local or proprietary coding systems, making it difficult to share, aggregate, or analyze across institutions. Manually mapping these disparate terminologies to a common standard such as OMOP requires deep domain expertise and is time‐consuming and error‐prone. OMOP MCP Server solves this problem by using large language models to automatically map clinical terms to standard OMOP concepts, significantly reducing the manual effort while maintaining high accuracy. It enables faster and more consistent data harmonisation, which is critical for collaborative research, regulatory submissions, and building large‐scale observational health data networks.
Use cases
- Mapping diagnosis codes from a hospital's custom dictionary to OMOP condition_concept_ids during ETL processes
- Standardizing medication names and dosages to OMOP drug concepts for a clinical research data mart
- Converting laboratory test names to LOINC codes and then to OMOP measurement concepts in real time
- Ingesting free‐text clinical notes and extracting conditions that are then normalized to OMOP standard concepts
- Building a terminology service that allows multiple applications to query LLM‐based mappings via an MCP interface
Audience
- Developers
- Data Scientists
- Researchers
Pros
- Automates tedious manual terminology mapping tasks
- Integrates seamlessly with AI agents through the Model Context Protocol
- Configurable to work with different LLM backends, balancing cost and accuracy
- Open source and self‐hostable, ensuring data privacy
- Docker support simplifies deployment and scaling
Cons
- LLM‐based mappings may require manual review for critical applications
- Effectiveness depends on the chosen LLM model and prompt engineering
- Limited to the terms understood by the configured models; rare or novel terms might fail
Official website: https://github.com/OHNLP/omop_mcp
Canonical LambdaBase page: https://www.lambdabase.com/tools/ohnlp-omopmcp