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MDR (MedDRA) - Metathesaurus Representation


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

VSAB: MDR26_0


Summary of Changes:

There were no changes to the original file format or to Metathesaurus source processing.


Source Provided Files:

The UMLS uses MedDRA files distributed in the MedAscii directory:
  • hlgt.asc
  • hlgt_hlt.asc
  • hlt.asc
  • hlt_pt.asc
  • intl_ord.asc
  • llt.asc
  • mdhier.asc
  • pt.asc
  • smq_content.asc
  • smq_list.asc
  • soc.asc
  • soc_hlgt.asc

Identifiers:

Overview: Lower Level Terms ("LLT"s) in MedDRA have any of the following relationships to their "PT":

  • Synonyms: Different terms for the same concept inherent in the "PT" (e.g., "PT" Arthritis and its subordinate "LLT" Joint inflammation)
  • Lexical variants: Different word forms for the same expression. These include full names vs. abbreviations and direct vs. inverted word order (e.g., "PT" Acquired immunodeficiency syndrome and its subordinate "LLT" AIDS or "PT" Biopsy tongue and its subordinate "LLT" Tongue biopsy).
  • Quasi-synonyms: Quasi-synonyms are terms that are not precisely the same meaning as another term, but are treated as synonymous in a given terminology. These include site and laterality descriptions (e.g., "PT" Otitis externa and its subordinate "LLT" Bilateral otitis externa).
  • Sub-element: Sub-elements (of the parent "PT") are represented by "LLT"s with more detailed information such as anatomic specificity (e.g., "PT"Contusion with "LLT" Bruising of face or "LLT" Bruising of leg).
  • Identical "LLT": One "LLT" is identical to its "PT" for data entry purposes (e.g., "PT" Dementia Alzheimer’s type and its subordinate "LLT" Dementia Alzheimer’s type). In this instance, the "LLT" and parent "PT" have the same MedDRA code but appear at both levels.

Since MedDRA does not indicate which "LLT"s share the same meaning with their "PT", all "LLT"s are assigned the same the same Source-asserted Descriptor Identifer (SDUI).  A descriptor is a collection of concepts (or atoms if there is no concept level organization) that are considered to be closely related (but not necessarily synonymous).

Identifiers are assigned as follows:

  • CODE: Populated by the "code" fields in original data files, e.g. the code for an "LLT" or "OL" atom comes from the llt_code field in llt.asc
  • SAUI: Not Applicable
  • SCUI: Not Applicable
  • SDUI: Populated by the "code" fields in original data files, except for TTY = "LLT" and TTY = "OL", where the pt_code field from llt.asc is used. This is because every "PT" has one identical "LLT" for data entry purposes. In addition, LLTs may be synonyms, lexical variants, quasi-synonyms, or sub-elements of their "PT". Therefore, the pt_code is represented in MRCONSO as a Source-asserted Descriptor Identifier (SDUI), indicating that the "LLT" and "PT" are closely related but not necessarily synonymous.

Atoms (MRCONSO):

Term Type Origin
AB CODE = soc_code field of soc.asc
STR = soc_abbrev field of soc.asc
SDUI = soc_code field of soc.asc
HG CODE = hlgt_code field of hlgt.asc
STR = hlgt_name field of hlgt.asc
SDUI = hlgt_code field of hlgt.asc
HT CODE = hlt_code field of hlt.asc
STR = hlt_name field of hlt.asc
SDUI = hlt_code field of hlt.asc
LLT CODE = llt_code field of llt.asc
STR = llt_name field of llt.asc
SDUI = pt_code field of llt.asc
MTH_HG CODE = hlgt_code field of hlgt.asc
STR = hlgt_name field of hlgt.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = hlgt_code field of hlgt.asc.
This data is added during Metathesaurus source processing.
MTH_HT CODE = hlt_code field of hlt.asc
STR = hlt_name field of hlt.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = hlt_code field of hlt.asc.
This data is added during Metathesaurus source processing.
MTH_LLT CODE = llt_code field of llt.asc
STR = llt_name field of llt.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = pt_code field of llt.asc.
LLT atoms are created where llt_currency field of llt.asc = "Y"
This data is added during Metathesaurus source processing.
MTH_OL CODE = llt_code field of llt.asc
STR = llt_name field of llt.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = pt_code field of llt.asc.
SUPRESS = "Y"
OL atoms are created where llt_currency field of llt.asc = "Y"
This data is added during Metathesaurus source processing.
MTH_OS CODE = soc_code field of soc.asc
STR = soc_name field of soc.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = soc_code field of soc.asc
This data is added during Metathesaurus source processing.
MTH_PT CODE = pt_code field of pt.asc
STR = pt_name field of pt.asc, with Americanization or abbreviation expansion algorithmn applied
SDUI = pt_code field of pt.asc
This data is added during Metathesaurus source processing.
MTH_SMQ CODE = smq_code field of SMQ_List.asc
STR = smq_name field of SMQ_List.asc, with Americanization or abbreviation expansion algorithm applied
SDUI = smq_code field of SMQ_List.asc
This data is added during Metathesaurus source processing.
OL CODE = llt_code field of llt.asc
STR = llt_name field of llt.asc
SDUI = pt_code field of llt.asc
SUPPRESS = "Y"
OL atoms are created where llt_currency field of llt.asc = "N"
OS CODE = soc_code field of soc.asc
STR = soc_name field of soc.asc
SDUI = soc_code field of soc.asc
PT CODE = pt_code field of pt.asc
STR = pt_name field of pt.asc
SDUI = pt_code field of pt.asc
SMQ CODE = smq_code field of SMQ_List.asc
STR = smq_name field of SMQ_List.asc
SDUI = smq_code field of SMQ_List.asc

Attributes (MRSAT):

Attribute Name Origin
MISO Serial code for international System Organ Class sort order. Extracted from the intl_ord_code field of intl_ord.asc.
MPS The primary System Organ Class to which a preferred term is linked. Extracted from the pt_soc_code field of pt.asc.
SMQ_ALGO Extracted from the SMQ_Algorithm field of SMQ_List.asc
SMQ_LEVEL Extracted from the SMQ_level field of SMQ_List.asc
SMQ_SOURCE Extracted from the SMQ_source field of SMQ_List.asc
SMQ_STATUS Extracted from the Status field of SMQ_List.asc
SMQ_TERM_ADDVERSION Extracted from the Term_addition_version field of SMQ_Content.asc
SMQ_TERM_CAT Extracted from the Term_category field of SMQ_Content.asc
SMQ_TERM_LEVEL Extracted from the Term_level field of SMQ_Content.asc
SMQ_TERM_LMVERSION Extracted from the Term_last_modified_version field of SMQ_Content.asc
SMQ_TERM_SCOPE Extracted from the Term_scope field of SMQ_Content.asc
SMQ_TERM_STATUS Extracted from the Term_status field of SMQ_Content.asc
SMQ_TERM_WEIGHT Extracted from the Term_weight field of SMQ_Content.asc
SOS Extracted from the SMQ_note field of SMQ_List.asc

Definitions (MRDEF):

ORIGIN
Extracted from the SMQ_description field of smq_list.asc. DEFINITIONs are present only for TTY = "SMQ", and include a description of the SMQ including inclusion and exclusion criteria.

Relationships (MRREL):

Relationship Relationship Label/Inverse Relationship Label ORIGIN
CHD
PAR
(no rela) Hierarchy extracted from hlt_pt.asc, hlgt_hlt.asc, soc_hlgt.asc files (can also be computed from mdhier.asc).
RQ classifies/classified_by Connects a "PT" to its "LLT"s or "OL"s. Data is derived from the llt_code and pt_code fields of llt.asc.
RO has_member/member_of Connects a Standardised MedDRA Query (SMQ) with subordinate terms. Derived from the SMQ_code and Term_code fields of SMQ_content.asc.
SY expanded_form_of/has_expanded_form Connects atoms with TTY = "OS" (Organ System) to their short forms (TTY = "AB").
SY mth_british_form_of/mth_has_british_form Connects atoms with British spelling to atoms with American spelling. This data is added during Metathesaurus source processing.
SY mth_has_expanded_form/mth_expanded_form_of Connects original MedDRA atoms with atoms with expanded abbreviations. For example, "excl" has been expanded to "excluding". This data is added during Metathesaurus source processing.