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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 Chemical19560728.8
T116Amino Acid, Peptide, or Protein12663618.6
T121Pharmacologic Substance9850914.5
T123Biologically Active Substance7020010.3
T004Fungus457906.7
T126Enzyme287544.2
T007Bacterium192702.8
T047Disease or Syndrome116951.7
T114Nucleic Acid, Nucleoside, or Nucleotide104561.5
T130Indicator, Reagent, or Diagnostic Aid78161.1
T129Immunologic Factor76921.1

Term Type Counts

Term TypeExpanded FormCount
NMName of Supplementary Concept318441
CEEntry term for a Supplementary Concept314016
PMMachine permutation127090
PCEPreferred entry term for Supplementary Concept77358
ETEntry term69329
MHMain heading30194
PEPPreferred entry term29246
N1Chemical Abstracts Service Type 1 name of a chemical22755
DEVDescriptor entry version16086
DSVDescriptor sort version3920
PXQPreferred qualifier term155
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 identifier965977
THMeSH Thesaurus ID - identifies thesauri other than MeSH in which the MeSH heading or cross-reference is included.883626
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)428626
RNRegistry Number - series of numbers and hyphens (any leading zeros in an RN are dropped) or a series of numbers and periods, preceded by EC378151
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.348711
SCMeSH Supplemental record class.318441
FRMeSH Frequency318416
MMRMeSH revision date YYYYMMDD - date of the last major revision to the term's MeSH record.275777
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)251721
SOSScope Statement214909
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.62406
PIMeSH heading or heading/subheading combination(s) followed by a date range in parentheses (YYYY).54972
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.46488
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.43397
DCMeSH Descriptor class - type of MeSH term the concept name represents.30194
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.30194
AQLMeSH Allowable Qualifier - list of allowable qualifier abbreviations for MeSH main headings (e.g. AA, CL, CS, DF, DU, IM, I,P ME, PK)28971
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.26244
PMPublic MeSH note - combines key information from the HN and PI elements in a format that is printed in the MeSH publications.25734
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)15856
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.15013
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.12581
FXMeSH MH Mapping - maps a MeSH MH to a 'See Related' MH.9026
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.3039
ECSpecifies the MeSH main heading to be used instead of the Descriptor/Qualifier combination specified in the EC_OF attribute.981
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 attribute616335
AQ/Allowed qualifier/Empty relationship attribute616335
RN/mapped_tohas a narrower relationship/Mapped to428626
RB/mapped_fromhas a broader relationship/Mapped from428626
SY/has_permuted_termsource asserted synonymy./Has permuted term127090
SY/permuted_term_ofsource asserted synonymy./Permuted term of127090
RB/has a broader relationship/Empty relationship attribute98888
RN/has a narrower relationship/Empty relationship attribute98888
PAR/has parent relationship in a Metathesaurus source vocabulary /Empty relationship attribute41308
CHD/has child relationship in a Metathesaurus source vocabulary /Empty relationship attribute41308
RO/mapping_qualifier_ofhas relationship other than synonymous, narrower, or broader/Mapping qualifier of35147
RO/has_mapping_qualifierhas relationship other than synonymous, narrower, or broader/Has mapping qualifier35147
RO/has relationship other than synonymous, narrower, or broader/Empty relationship attribute28986
SY/has_entry_versionsource asserted synonymy./Has entry version16164
SY/entry_version_ofsource asserted synonymy./Entry version of16164
RB/inverse_isahas a broader relationship/Inverse is a15013
RN/isahas a narrower relationship/Is a15013
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
32408

Source Overlap

Source# Concepts Sharing Atom/# Total ConceptsPercentage Distribution
NCBI69932/45567215.3
MSHFRE48535/45567210.7
MSHCZE48725/45567210.7
MSHGER44558/4556729.8
MSHPOR43432/4556729.5
MSHSPA42713/4556729.4
MSHITA39794/4556728.7
SNOMEDCT_US39185/4556728.6
SCTSPA38425/4556728.4
MSHSWE36157/4556727.9
MSHNOR33817/4556727.4
NCI33061/4556727.3
MSHPOL30201/4556726.6
MSHRUS30206/4556726.6
MSHJPN24857/4556725.5
CHV24629/4556725.4
MSHFIN24691/4556725.4
SNMI21389/4556724.7
MSHDUT20587/4556724.5
RCD17180/4556723.8
NCI_FDA11323/4556722.5
SNM10765/4556722.4
CSP10803/4556722.4
LCH_NW10364/4556722.3
RXNORM10043/4556722.2
MEDCIN10246/4556722.2
MSHSCR9141/4556722.0
OMIM8189/4556721.8
LNC7240/4556721.6
MDRJPN7279/4556721.6
MDR7292/4556721.6
MDRBPO7292/4556721.6
MDRCZE7292/4556721.6
MDRDUT7292/4556721.6
MDRFRE7292/4556721.6
MDRGER7292/4556721.6
MDRHUN7292/4556721.6
MDRITA7292/4556721.6
MDRKOR7292/4556721.6
MDRPOR7292/4556721.6
MDRRUS7292/4556721.6
MDRSPA7292/4556721.6
AOD7313/4556721.6
DRUGBANK6323/4556721.4
NDDF6389/4556721.4
MMSL6420/4556721.4
PDQ6506/4556721.4
NCI_CTRP5468/4556721.2
LCH5640/4556721.2
MTHSPL5087/4556721.1