This document reflects the requirements and implementation for the Standardized Vocabularies which are part of the OMOP Common Data Model (CDM), version 5.0. They are maintained by the Observational Health Data Science and Informatics (OHDSI, pronounced Odyssey) collaborative and financially supported by the Innovative XXX (IMEDS) program of the Reagan-Udall Foundation for the FDA. Patient-level data available in OMOP CDM explicitly require the representation of all clinical facts and events using Concepts from the Standardized Vocabularies. Therefore, the Standardized Vocabularies are an integral part of the OMOP CDM. It is available for free to anyone and can be downloaded from the Download page. Generally, all parts and components are Open Source under, unless otherwise specified for a very few commercial vocabularies. Please see Apache License V2.0 for details. The Standardized Vocabularies provide a standardized representation of data in the following clinical domains.

• Demographics: Gender, Ethnicity, Race
• Condition
• Drug
• Procedure
• Measurement
• Observation
• Note
• Device
• Specimen
• Visit
• Death
• Provider
• Cost

Currently, 61 vocabularies are part of the Standardized Vocabularies. Many of them are adopted from 3rd party sources developing and maintaining for specific purpose. Consolidation of the vocabularies into a standardized form requires a number of decisions and conventions. This document discusses both the organization of vocabularies within the clinical domains, as well as the specific implementation of each vocabulary into the Standardized Vocabularies, as well as the mapping of Concepts within and between vocabularies. It also provides guidance of how to apply them for transformation of data into the CDM and the querying of data once they are established in CDM format.

The audiences for this document are researchers and developers who want to utilize the OMOP CDM for observational outcome research.

The Standardized Vocabularies are now released in Version 5.0. There have been changes to the previous versions, without violating any of the design principles. In particular, all concepts in previous versions are still available and identified using the same Concept IDs. New data domains were added to the concept list (Device, Measurement, Specimen) and all concepts are now formally assigned a Domain.