When adding a new HTA External Code System Information page ensure that a row for the code system is added to the index at the following link: HTA — External Terminologies - Information – Code System Metadata Records Index

Data element name

Sub data element name


Code System Owner

NameU.S. Department of Veterans Affairs, Veterans Health Administration
Email addressN/A
Phone number1-800-698-2411
Address810 Vermont Ave NW, Washington, DC 20571, United States
Code System Maintainer (Steward)NameN/A (No Longer Maintained)
Email address
Phone number
Code System PublisherNameNational Cancer Institute  
Email addressNCIAppSupport@nih.gov
Phone number1-240-276-5541
Code System NamesFormal name of the code systemNational Drug File – Reference Terminology
Short name of the code systemNDF-RT
Code System Technical IdentifiersHTA-endorsed URIhttp://hl7.org/fhir/ndfrt
HTA-endorsed OID2.16.840.1.113883.6.209
Other URIs
Other OIDs
Case Sensitive Codes (TRUE/FALSE)TRUE (default value)
Code System InformationLink



Production and publication of NDF-RT has ceased with the February 2018 release. From March 2018, the MED-RT terminology replaced NDF-RT.

NDF-RT is a concept-oriented terminology, a collection of concepts, each of which represents a single, unique meaning. Every concept has one fully-specified name and an arbitrary number of other names, all of which are intended to mean the same thing and are therefore synonymous terms. Synonymous terms from external vocabulary sources may have associated unique identifiers. Additionally, NDF-RT assigns an alphanumeric unique identifier (NUI) to every concept, maintained across releases to label and track that meaning.

Concepts in NDF-RT are organized into taxonomies, that is, hierarchies of concepts based on generalization. The meaning of each concept within a taxonomy is both more general than the meanings of its descendants (if any) and more specific than the meanings of its ancestors (if any).

As a reference terminology and ontology, NDF-RT provides a formal content model that describes and defines medications, both computationally and to humans, by naming relevant concepts via preferred and synonymous terms, and describing them via named relations to other terminology concepts, either within NDF-RT or in external terminologies. By content model, we mean the specific concepts and kinds, role and associational relationships, and conceptual properties in a reference terminology and ontology. Assuming a basic knowledge of content modeling and representational elements, the next sections flesh out the specific content model of NDF-RT.

In NDF-RTTM, generic ingredients or combinations thereof are described in terms of their active ingredients, mechanisms of action, physiologic effects, and therapeutics (indications and contraindications). Orderable (clinical) drug products inherit the descriptions of their generic ingredients, and are further described by local (VHA) drug classification, strength, units, and dose forms. All of the descriptive concepts can themselves be explained via their position in hierarchical classifications or taxonomies of related concepts.

Further information available from https://evs.nci.nih.gov/ftp1/NDF-RT/

Arrangement or agreements with HL7 for use of content

Version management

NDF-RT was published ten times per calendar year with combined releases occurring in December/January and August/September.

To assert a particular version, the date (in YYYYMMDD format) for the release may be used. 

Code System Copyright, Intellectual Property and LicensingCopyright Statement
Copyright InformationNDF-RT has no copyright acknowledgement required. However, users must adhere to the UMLS license.
Intellectual Property Information
Licensing Information
HTA endorsement status (Draft, In review, Endorsed for use, Pending re-endorsement, Retired) ValueDraft
Assignment date20220811
HTA review statusLast review date20220811
Next review date20230811
Information current as at (date)
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