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Unified Medical Language System (UMLS)

UMLS Vocabularies

MSH (MeSH) - Statistics


Semantic Type Distribution

Semantic Type IDSemantic Type NameCount Percentage Distribution
T109Organic Chemical19219232.0
T116Amino Acid, Peptide, or Protein12378720.6
T121Pharmacologic Substance9474815.8
T123Biologically Active Substance6867011.4
T126Enzyme281244.7
T047Disease or Syndrome115071.9
T114Nucleic Acid, Nucleoside, or Nucleotide101081.7
T130Indicator, Reagent, or Diagnostic Aid77201.3
T129Immunologic Factor68691.1

Term Type Counts

Term TypeExpanded FormCount
CEEntry term for a Supplementary Concept277727
NMName of Supplementary Concept249560
PMMachine permutation120703
PCEPreferred entry term for Supplementary Concept75142
ETEntry term63502
MHMain heading29640
PEPPreferred entry term28369
N1Chemical Abstracts Service Type 1 name of a chemical22923
DEVDescriptor entry version16117
DSVDescriptor sort version3920
PXQPreferred qualifier term158
QABQualifier abbreviation78
QEVQualifier entry version78
TQTopical qualifier76
XQAlternate name for a qualifier72
HTHierarchical term22
QSVQualifier sort version7
HSShort or alternate version of hierarchical term4

Attribute Counts

Attribute TypeExpanded FormCount
TERMUITerm unique identifier844949
THMeSH Thesaurus ID - identifies thesauri other than MeSH in which the MeSH heading or cross-reference is included.768290
HMMeSH Heading Mapped To - heading mapped to attribute in C-MeSH containing repeating (MH or MH/SH) elements (e.g. HM = PYRROLIDINONES, HM = *TARTRATES, HM = ESTRONE/* analogs & derivatives)356590
RNRegistry Number - series of numbers and hyphens (any leading zeros in an RN are dropped) or a series of numbers and periods, preceded by EC302319
MDAMeSH date of entry YYYYMMDD - date the term was added to the MeSH file, which is prior to the date the term became available for indexing and searching MEDLARS citations. Terms that have been part of MeSH for many years may have no value in this element.279276
SCMeSH Supplemental record class.249560
FRMeSH Frequency249517
SRCMeSH Literature source of chemical name - a citation to an article in a journal indexed for MEDLINE in which the chemical has been identified. (Note: Not to be confused with source abbreviation of SRC)248023
SOSScope Statement211370
MMRMeSH revision date YYYYMMDD - date of the last major revision to the term's MeSH record.203794
MNMeSH hierarchical number for the concept in the MeSH tree structures. This number also appears in the HCD subelement of the REL and CXT elements.60755
PIMeSH heading or heading/subheading combination(s) followed by a date range in parentheses (YYYY).51042
IIMeSH Indexing Information - for MeSH chemical terms (Term Type=NM), MeSH headings that may be relevant to articles that are also assigned the NM term.44912
RRThe Chemical Abstracts Registry numbers for salts, optical isomers, or isotope-labeled versions of the concept followed by the relationship of this RR to the RN (in parentheses.) Applies to chemicals only. These numbers can be used as links to information in a number of chemical and toxicological databases.40585
DCMeSH Descriptor class - type of MeSH term the concept name represents.29640
DXMeSH Date major descriptor established YYYYMMDD - first day of the Index Medicus publication month in which the descriptor (in any form) was available for searching as a major descriptor.29640
AQLMeSH Allowable Qualifier - list of allowable qualifier abbreviations for MeSH main headings (e.g. AA, CL, CS, DF, DU, IM, I,P ME, PK)28487
HNHistory Note - for MeSH history notes, the year when the current form of the MeSH term was established as a major and/or minor descriptor.25689
PMPublic MeSH note - combines key information from the HN and PI elements in a format that is printed in the MeSH publications.25181
LTIndicates if a chemicals or medical device is a tradename (present in older versions of the Metathesaurus and was discontinued, then brought back starting in 2002AD)15503
PAPharmacologic Action of MeSH main headings (MH) for drugs and supplementary concept names (NM). The information in this element is also represented by an "isa" relationship between the MH or NM concept and the MeSH concept name for the class of drugs with a particular pharmacologic action.14516
ANMeSH Annotation - an informative MeSH note written primarily for indexers or catalogers that may also be useful in explaining the use of a MeSH term to online searchers.12563
FXMeSH MH Mapping - maps a MeSH MH to a 'See Related' MH.8874
OLMeSH Online Note - information helpful to online searchers of MEDLINE, especially when the history of a term or cross-reference has implications for online searching. This is a potential source of useful information for rules for search interface programs.3055
ECSpecifies the MeSH main heading to be used instead of the Descriptor/Qualifier combination specified in the EC_OF attribute.982
DQMeSH Date Qualifier Established YYYYMMDD - date the qualifier became available for indexing MEDLARS citations.76
CXMeSH Consider Also Note - other word roots or prefixes that should be consulted for concepts related to this MeSH concept, e.g., the value for "Heart" is "consider also terms at cardi- and myocardi-".66

Relationship Counts

Relation Name/Additional LabelExpanded FormCount
QB/can be qualified by./Empty relationship attribute607384
AQ/Allowed qualifier/Empty relationship attribute607384
SIB/has sibling relationship in a Metathesaurus source vocabulary./Empty relationship attribute472842
RN/mapped_tohas a narrower relationship/Mapped to356590
RB/mapped_fromhas a broader relationship/Mapped from356590
SY/permuted_term_ofsource asserted synonymy./Permuted term of120703
SY/has_permuted_termsource asserted synonymy./Has permuted term120703
RN/has a narrower relationship/Empty relationship attribute96329
RB/has a broader relationship/Empty relationship attribute96329
PAR/has parent relationship in a Metathesaurus source vocabulary /Empty relationship attribute40477
CHD/has child relationship in a Metathesaurus source vocabulary /Empty relationship attribute40477
RO/mapping_qualifier_ofhas relationship other than synonymous, narrower, or broader/Mapping qualifier of34941
RO/has_mapping_qualifierhas relationship other than synonymous, narrower, or broader/Has mapping qualifier34941
RO/has relationship other than synonymous, narrower, or broader/Empty relationship attribute27734
SY/has_entry_versionsource asserted synonymy./Has entry version16195
SY/entry_version_ofsource asserted synonymy./Entry version of16195
RB/inverse_isahas a broader relationship/Inverse is a14516
RN/isahas a narrower relationship/Is a14516
SY/sort_version_ofsource asserted synonymy./Sort version of3927
SY/has_sort_versionsource asserted synonymy./Has sort version3927
SY/has_expanded_formsource asserted synonymy./Has expanded form78
SY/expanded_form_ofsource asserted synonymy./Expanded form of78

Definition Count

Count
31744

Source Overlap

Source# Concepts Sharing Atom/# Total ConceptsPercentage Distribution
MSHFRE47131/38281112.3
MSHCZE43566/38281111.4
MSHGER43679/38281111.4
MSHPOR40837/38281110.7
MSHSPA40585/38281110.6
MSHITA39807/38281110.4
MSHNOR33834/3828118.8
SNOMEDCT_US30819/3828118.1
SCTSPA30292/3828117.9
MSHPOL29350/3828117.7
MSHRUS29350/3828117.7
MSHSWE29423/3828117.7
NCI29528/3828117.7
MSHJPN24857/3828116.5
CHV24334/3828116.4
MSHFIN24691/3828116.4
MSHDUT20616/3828115.4
SNMI19778/3828115.2
RCD15919/3828114.2
CSP10745/3828112.8
SNM10306/3828112.7
LCH_NW10354/3828112.7
MEDCIN9440/3828112.5
NCI_FDA9502/3828112.5
MSHSCR9142/3828112.4
RXNORM9177/3828112.4
OMIM8024/3828112.1
AOD7239/3828111.9
LNC6813/3828111.8
MDRJPN6872/3828111.8
MDR6885/3828111.8
MDRCZE6885/3828111.8
MDRDUT6885/3828111.8
MDRFRE6885/3828111.8
MDRGER6885/3828111.8
MDRHUN6885/3828111.8
MDRITA6885/3828111.8
MDRPOR6885/3828111.8
MDRRUS6885/3828111.8
MDRSPA6885/3828111.8
MMSL5948/3828111.6
NDDF6091/3828111.6
PDQ6127/3828111.6
NCBI6169/3828111.6
DRUGBANK5585/3828111.5
LCH5627/3828111.5
MTHSPL4534/3828111.2
NCI_CTRP4683/3828111.2
ICPC2ICD10ENG4292/3828111.1