CDISC Terminology is the set of CDISC-developed or CDISC-adopted standard expressions (values) used with data items within the Foundational Standards and Therapeutic Area User Guides. CDISC Terminology provides context, content, and meaning to clinical research data and provides a consistent semantic layer across all operational contexts, enabling interoperability of the CDISC Standards. Each of the Foundational Standards’ data models includes terminology implementation requirements.

CDISC Terminology is published by the US National Cancer Institute’s Enterprise Vocabulary Services (NCI-EVS) as a set of terminology products that support the use of and harmonization among the CDISC Foundational Standards. These products include Protocol, SEND, CDASH, SDTM, ADaM, Define-XML, and Glossary. CDISC Terminology consists of submission values, definitions, synonyms, codelists, codes, and code system elements, which are needed to specify a complete terminology system.