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Unified Medical Language System (UMLS)

UMLS Vocabularies

PDQ (Physician Data Query) - Metathesaurus Representation

This page lists UMLS Metathesaurus data elements and traces them back to the specific source data that populates them.

VSAB: PDQ_2018_10_27

Summary of Changes

New TTY = BN (fully-specified drug brand name that CANNOT be prescribed). This replaces the previous TTY=BD (fully-specified drug brand name that CAN be prescribed).

Original Files:

File NameDescription
Terminology.tarWhen uncompressed there are a total of 13,407 individual xml files (CDR256085.xml, CDR256086.xml, CDR256087.xml, etc.)


  • SAUI: Not applicable
  • SCUI: Not applicable


Term TypeDescriptionOrigin
AB Abbreviation Abbreviation field
ACR Acronym Acronym field
BN US brand name Common usage field
CCN Chemical code name Chemcial code name field
CHN Chemical structure name Chemical structure name field
CU Common usage Common usage field
ET Display name Display name field
FBD Foreign brand name Foreign brand name field
HT Header term Header term field
IS Obsolete name Obsolete name field
LV Lexical variant Lexical variant field
OP Obsolete term Obsolete term field
PSC Protocol selection criteria Protocol selection criteria field
PT Preferred name Preferred name field
SY Synonym Synonym field


All term types have suppressibility value 'N' (default value) except for IS and OP which have suppressibility value 'O'.

Attributes (MRSAT)

Attribute NameOrigin
CAS_REGISTRY CAS Registry name field
DATE_FIRST_PUBLISHED DateFirstPublished field
DATE_LAST_MODIFIED DateLastModified field
IND_CODE IND code field
LEXICAL_TAG; value = LAB Chemical code name field
LEXICAL_TAG; value = TRD Foreign or US brand name field
MENU_PARENT MenuParent field
MENU_TYPE MenuType field
NCI_ID NCIMetathesaurusConceptID field
NSC_CODE NSC number field
ORIG_STY SemanticType field

Relationships (MRREL)

SourceRelationshipRelationship Label/Inverse Relationship LabelDescription
(no rela)Hierarchy created from the <ParentTerm> values
PDQNT tradename_of/has_tradenameConnects the brand name (TTY=BN/FBD) with its generic name.
PDQNT lab_number_of/has_lab_numberConnects the name (TTY=PT) with its chemical code name (TTY=CCN).
PDQRT associated_genetic_condition/associated_diseaseConnects the name (TTY=PT) with its RelatedTermName.
PDQRT has_component/component_ofConnects the name (TTY=PT) with its RelatedTermName.
PDQSFO/LFO has_expanded_form/expanded_form_ofConnects the name (TTY=PT) with its acronym (TTY=ACR).
PDQSY (no rela)Connects the name (TTY=PT) with its abbreviation (TTY=AB).

Definitions (MRDEF)

Definitions present.

Mappings (MRMAP)

There are no mappings present.