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XML MeSH Data Elements (2016)

The following is an alphabetic list of elements available for MeSH data in XML format, including Descriptors, Qualifiers, and Supplementary Concept Records. To fully understand these elements, it is recommended that you also review Introduction to MeSH in XML format. In particular, it is important to understand: (1) the three-level concept structure of MeSH data (Descriptors, Concepts, Terms), (2) reference to these objects by both a unique name and a unique identifier, and (3) the use of "list" elements in order to represent the structure of multiply-occurring elements. MEDLINE XML element descriptions are also available.

Note that some elements formerly available only in XML MeSH are now available in the MeSH Browser. See About MeSH Browser.

Key to element information:

RecordType
: may appear in records of the following types:
D = Descriptor
Q = Qualifier
SCR = Supplementary Concept Record

Repeating element
: may occur more than once within a record.
Required element
: all records in the given Record Types have the element.
MeSH Browser: element label in the MeSH Browser, or "none" .
ASCII MeSH: data element, usually with element name, or "none".
ELHILL MeSH
: element mnemonic and number in ELHILL MeSH (obsolete), or "none" .

 

  1. <Annotation>
    Description: Free-text information for indexers and catalogers concerning the use of the <DescriptorRecord> or <QualifierRecord> in PubMed.
    Example:
    <Annotation>coord with DNA or RNA or specific</Annotation>
    Subelement of: <DescriptorRecord>
    Record Type: D, Q
    Repeating element: no
    Required element: no
    MeSH Browser: Annotation
    ASCII MeSH: AN (ANNOTATION)
    ELHILL MeSH: AN (260)

  2. <Abbreviation>
    Description: Two-letter abbreviation for Qualifier terms.
    Example:
    <Abbreviation>GE</Abbreviation
    Subelement of: <Term>, <AllowableQualifier>
    Record Type: Q, D
    Repeating element: yes
    Required element: no
    MeSH Browser: Abbreviation; Allowable Qualifiers
    ASCII MeSH: QA (TOPICAL QUALIFIER ABBREVIATION)
    ELHILL MeSH: QA (216); AQ (398)

  3. <AllowableQualifier>
    Description: A specific Qualifier allowed in combination with the Descriptor for indexing.
    Example:
    <AllowableQualifier>
    <QualifierReferredTo>
    <QualifierUI>Q000819</QualifierUI>
    <QualifierName>
    <String>agonists</String>
    </QualifierName>
    </QualifierReferredTo>
    <Abbreviation>AG</Abbreviation>
    </AllowableQualifier>
    Subelement of: <AllowableQualifiersList>
    Record Type: D
    Repeating element: yes
    Required element: no
    MeSH Browser: Allowable Qualifiers
    ASCII MeSH: AQ (ALLOWABLE TOPICAL QUALIFIERS)
    ELHILL MeSH: AQ (398)

  4. <AllowableQualifiersList>
    Description: List of multiple occurrences of the <AllowableQualifier> element for a given <DescriptorRecord>.
    Example:
    <AllowableQualifiersList>
    <AllowableQualifier>
    ...
    </AllowableQualifier>
    </AllowableQualifiersList>
    Subelement of: <DescriptorRecord>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: Allowable Qualifiers
    ASCII MeSH: AQ (ALLOWABLE TOPICAL QUALIFIERS)
    ELHILL MeSH: AQ (398)

  5. <CASN1Name>
    Description: Chemical Abstracts Type N1 Name. A free-text element containing the systematic name used in the Chemical Abstracts Chemical Substance and Formula Indexes. The systematic name is a unique name assigned to a chemical substance to represent its structure. First available for Descriptors in 1995.
    Example:
    <CASN1Name>1,3-Butadiene, 2-chloro-, homopolymer</CASN1Name>
    Subelement of: <Concept>
    Record Type: D, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: CAS Type 1 Name [as concept attribute in the Descriptor Enhanced Concept View]
    ASCII MeSH: N1 (CAS TYPE 1 NAME)
    ELHILL MeSH: N1 (614)

  6. <Concept>
    Description: The bearer of linguistic meaning in MeSH as defined by the <ScopeNote>, comprising a <DescriptorRecord> or <SupplementalRecord> or <QualifierRecord>, and consisting of <Term> elements. One of the three main objects in the MeSH XML (the others being the record, and term). A single record will have one or more concepts, one of which is the preferred concept of the record. A Concept will have one or more terms, one of which is the preferred term for the concept. Referred to uniquely by both a <ConceptUI> and a <ConceptName>.
    Example:
    <Concept PreferredConceptYN="Y">
    <ConceptUI>M0000001</ConceptUI>
    <ConceptName>
    <String>Calcimycin</String>
    </ConceptName>
    <ScopeNote>An ionophorous, polyether antibiotic from Streptomyces chartreusensis. ...
    </ScopeNote>
    <TermList>
    ...
    </TermList>
    </Concept>
    Subelement of: <ConceptList>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Concept 1, etc. [only in the two Descriptor Concept views]
    ASCII MeSH: none
    ELHILL MeSH: none

  7. <Concept1UI>
    Description: The <ConceptUI> of first concept in the <ConceptRelation> element, referring to the parent concept.

    Subelement of: <ConceptRelation>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  8. <Concept2UI>
    Description: The <ConceptUI> of second concept in the <ConceptRelation> element.

    Subelement of: <ConceptRelation>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  9. <ConceptList>
    Description: Set of one or more <Concept> elements in a Descriptor, Qualifier, or Supplementary Concept record.

    Subelement of: <DescriptorRecord>; <QualifierRecord>; <SupplementalRecord>
    Record Type: D, Q, SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  10. <ConceptName>
    Description: The <Term> that uniquely names the <Concept> and, along with the <ConceptName>, is used to represent the Concept in other elements. The same term as the preferred term of the concept.

    Subelement of: <Concept>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: [only in the two Descriptor Concept views]
    ASCII MeSH: none
    ELHILL MeSH: none

  11. ConceptPreferredTermYN
    Description: Attribute of the <Term> element which indicates whether or not the term is the preferred term of its concept. See Introduction to MeSH in XML format.
    Example:
    <Term ConceptPreferredTermYN="Y"
    IsPermutedTermYN="N"
    LexicalTag="NON"
    RecordPreferredTermYN="Y">
    <TermUI>T000002</TermUI>
    <String>Calcimycin</String>
    ...
    </Term>
    Subelement of: not applicable; attribute of <Term>
    Record Type: D, Q, SCR
    Repeating attribute: yes
    Required attribute: yes
    MeSH Browser: Preferred [in the Descriptor Expanded Concept View; first term in the Standard Concept View]
    ASCII MeSH: none
    ELHILL MeSH: none

  12. <ConceptRelation>
    Description: A semantic relation between a given <Concept> and another <Concept>. The most common case currently is the semantic relation between the preferred concept and subordinate concept(s) in the same record. The type of relation is specified by the attribute RelationName, which consists of one of the following values:
    ValueMeaning
    BRD (broader)
    NRW (narrower)
    REL (related but not broader or narrower)

    Example:
    <ConceptRelation RelationName="NRW">
    <Concept1UI>M0000001</Concept1UI>
    <Concept2UI>M0353609</Concept2UI>
    </ConceptRelation>
    In this example the concept M0353609 has the relation NRW with respect to concept M0000001. That is, M0353609 (A-23187) is narrower than M0000001 (Calcimycin). Currently the maximum number of relations per concept is one. And the minimum number of relations per non-preferred concept is one.


    Subelement of: <ConceptRelationList>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Preferred, Narrower, Related [only in the two Descriptor Concept views]
    ASCII MeSH: ENTRY (NON-PRINT ENTRY TERM), PRINT ENTRY subfield
    ELHILL MeSH: none

  13. <ConceptRelationList>
    Description: The set of one or more named relations between a given <Concept> and another <Concept>. The name of the relation is specified by the RelationName attribute of the subelement <ConceptRelation>, e.g., NRW, etc.

    Subelement of: <Concept>
    Record Type: D, Q, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: none, but see <ConceptRelation>.
    ASCII MeSH: none
    ELHILL MeSH: none

  14. <ConceptUI>
    Description: Concept Unique Identifier. Eight-character alpha-numeric string uniquely identifying a <Concept> and, along with the <ConceptName>, is used to represent the <Concept> in other elements.
    Example:
    <ConceptUI>M0003047</ConceptUI>
    Subelement of: <Concept>
    Record Type: D, Q, SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: Concept UI [only in the Descriptor Expanded Concept View]
    ASCII MeSH: none
    ELHILL MeSH: none

  15. <ConsiderAlso>
    Description: Consider Also cross-reference. Free-text element which refers a user from a Descriptor to other terms which have related roots. For example, the CX entry for BLOOD is:
    <ConsiderAlso>consider also terms at HEM-</ConsiderAlso>
    Subelement of: <DescriptorRecord>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: Consider Also
    ASCII MeSH: CX (CONSIDER ALSO XREF)
    ELHILL MeSH: CX (569)

  16. <DateCreated>
    Description: Date when a <Term> or record was first entered in the MeSH data entry system. A time-stamp, which may be a year behind the <DateEstablished>. Note that when data were converted to the new MeSH maintenance system in 1999, many terms did not have a <DateCreated> value and so were given a value of January 1, 1999. Similar in format to the MEDLINE element of the same name.
    Example:
    <DateCreated>
    <Year>1990</Year>
    <Month>03</Month>
    <Day>08</Day>
    </DateCreated>
    Subelement of: <DescriptorRecord>; <Term>
    Record Type: D, Q, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: Date of Entry
    ASCII MeSH: DA (DATE OF ENTRY); ENTRY (NON-PRINT ENTRY TERM), PRINT ENTRY subfield
    ELHILL MeSH: DA (100); BX (277) subfield

  17. <DateEstablished>
    Description: First day of the first full month when a <DescriptorRecord> or <QualifierRecord> first becomes available for searching in NLM's online databases, such as PubMed. (Formerly the first year published in Index Medicus.) Usually the records introduced in a given MeSH year will have the same <DateEstablished>.
    Example:
    <DateEstablished>
    <Year>2001</Year>
    <Month>01</Month>
    <Day>01</Day>
    </DateEstablished>
    Subelement of: <DescriptorRecord>; <QualifierRecord>
    Record Type: D, Q
    Repeating element: no
    Required element: yes
    MeSH Browser: Date Established [only in Qualifiers]
    ASCII MeSH: DX (DATE MAJOR DESCRIPTOR ESTABLISHED), DQ (DATE QUALIFIER ESTABLISHED)
    ELHILL MeSH: DX (264); DQ (354)

  18. <DateRevised>
    Description: Date when a record was last changed. Similar in format to the MEDLINE element of the same name.
    Example:
    <DateRevised>
    <Year>2000</Year>
    <Month>06</Month>
    <Day>21</Day>
    </DateRevised>
    Subelement of: <DescriptorRecord>
    Record Type: D, Q, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: Revision Date [SCRs and Qualifiers]
    ASCII MeSH: MR (MAJOR REVISION DATE)
    ELHILL MeSH: MR (120)

  19. <Day>
    Description: Two-character string giving the day of the month. Similar in format to the MEDLINE element of the same name.

    Subelement of: <DateCreated>; <DateRevised>; <DateEstablished>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  20. DescriptorClass
    Description: Attribute of <DescriptorRecord> having as a value one of four numbers indicating whether a record is (a) a topical Descriptor, used to identify the subject of an indexed document, or (b) a non-topical Descriptor. There are four possible DC values:
    • 1 = Topical Descriptor.
    • 2 = Publication Types, for example, 'Review'.
    • 3 = Check Tag, e.g., 'Male' (no tree number)
    • 4 = Geographic Descriptor (Z category of tree number).
    This element is not to be confused with the set or class of <Concept> elements in a Descriptor which may also be referred to as the Descriptor Class of that record.
    Example:
    <DescriptorRecord DescriptorClass = "1">
    Subelement of: not applicable . Attribute of <DescriptorRecord>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: DC (DESCRIPTOR CLASS)
    ELHILL MeSH: DC (250)

  21. <DescriptorName>
    Description: A term that uniquely refers to its <DescriptorRecord> and, along with the <DescriptorUI>, is used to represent the Descriptor in other elements, by the <DescriptorReferredTo>. The same term as the preferred <Term> of the preferred <Concept>. Comparable to, and the source of, the MEDLINE element of the same name. (Note that the MEDLINE element has different attributes.)

    Subelement of: <DescriptorRecord>; <DescriptorReferredTo>.
    Record Type: D, Q, SCR
    Example:
    <DescriptorName>
    <String>Calcimycin></String>
    </DescriptorName>
    Repeating element: yes
    Required element: yes
    MeSH Browser: MeSH Heading
    ASCII MeSH: MH
    ELHILL MeSH: MH (251)

  22. <DescriptorRecord>
    Description: Cluster of one or more concepts used for subject indexing and retrieval. Identified uniquely by a <DescriptorUI> and <DescriptorName>. A Descriptor. A Descriptor record. Also known as Main Heading. (Note that this differs from the MEDLINE <MeshHeading> element. For example, the MEDLINE element includes both the Descriptor name and the Qualifier name assigned to a citation.)
    Example:
    <DescriptorRecord DescriptorClass = "1">

    ...

    </DescriptorRecord>

    Subelement of: <DescriptorRecordSet>
    Record Type: D
    Repeating element: yes
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  23. <DescriptorRecordSet>
    Description: The set of all <DescriptorRecord> elements in the Descriptor XML file.

    Subelement of: none; this is the root element.
    Record Type: D
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  24. <DescriptorReferredTo Description: The pair of elements <DescriptorUI> and <DescriptorName> each of which uniquely refers to a <DescriptorRecord>. Used to represent the <DescriptorRecord> in other elements.
    Example:
    <DescriptorReferredTo>
    <DescriptorUI>D000900</DescriptorUI>
    <DescriptorName>
    <String>Antibiotics</String>
    </DescriptorName>
    </DescriptorReferredTo>
    Subelement of: <ECIN>; <ECOUT>; <SeeRelatedDescriptor>; <PharmacologicalAction>; <HeadingMappedTo>.
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  25. <DescriptorUI>
    Description: Descriptor Unique Identifier. Seven-character alpha-numeric string uniquely identifying a <DescriptorRecord> and, along with the <DescriptorName>, is used to represent the <DescriptorRecord> in other elements, by the <DescriptorReferredTo>.
    Example:
    <DescriptorUI>D000001</DescriptorUI>
    Subelement of: <DescriptorRecord>; <DescriptorReferredTo>.
    Record Type: D, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Unique ID
    ASCII MeSH: UI (UNIQUE IDENTIFIER)
    ELHILL MeSH: UI (480)

  26. <ECIN>
    Description: Descriptor/Qualifier combination prohibited in the <EntryCombination> of a given <DescriptorRecord>. Example: See <EntryCombination>.
    Subelement of: <EntryCombination>
    Record Type: D
    Repeating element: yes
    Required element: no
    MeSH Browser: Entry Combination
    ASCII MeSH: EC (ENTRY COMBINATION) subelement
    ELHILL MeSH: EC (270) subelement

  27. <ECOUT>
    Description: Descriptor or Descriptor/Qualifier combination recommended in place of the prohibited combination in the <EntryCombination> of a given <DescriptorRecord>.
    Example: See <EntryCombination>.
    Subelement of: <EntryCombination>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Entry Combination
    ASCII MeSH: EC (ENTRY COMBINATION)subelement
    ELHILL MeSH: EC (270) subelement

  28. <EntryCombination>
    Description: A reference to a specific Qualifier that is not to be used with the Descriptor in indexing. The <ECIN> element specifies the Qualifier and Descriptor combination that is prohibited. Instead of this combination, another Descriptor is to be used, specified by the <ECOUT> element. For example, in the Descriptor for 'Abdomen', the <ECIN> refers to the use of 'Abdomen' with 'radiography' and the <ECOUT> specifies the Descriptor 'Radiography, Abdominal'. This means that the combination of 'Abdomen' and 'radiography' is prohibited but instead 'Radiography, Abdominal' should be used. The <ECOUT> element may also be a Descriptor/Qualifier combination as well as a Descriptor. As in most of XML MeSH, the Descriptor and Qualifier are referred to both by the Unique Identifier of the record as well as the term that names the record.
    Example:
    <EntryCombination>
    <ECIN>
    <DescriptorReferredTo>
    <DescriptorUI>D000005</DescriptorUI>
    <DescriptorName>
    <String>Abdomen</String>
    </DescriptorName>
    </DescriptorReferredTo>
    <QualifierReferredTo>
    <QualifierUI>Q000530</QualifierUI>
    <QualifierName>
    <String>radiography</String>
    </QualifierName>
    </QualifierReferredTo>
    </ECIN>
    <ECOUT>
    <DescriptorReferredTo>
    <DescriptorUI>D011860</DescriptorUI>
    <DescriptorName>
    <String>Radiography, Abdominal</String>
    </DescriptorName>
    </DescriptorReferredTo>
    </ECOUT>
    </EntryCombination>
    Subelement of: <EntryCombinationList>
    Record Type: D
    Repeating element: yes
    MeSH Browser: Entry Combination
    Required element: no
    ASCII MeSH: EC (ENTRY COMBINATION)
    ELHILL MeSH: EC (270)

  29. <EntryCombinationList>
    Description: The set of one or more <ECIN> and <ECOUT> pairs in the <EntryCombination> element.
    Subelement of: <DescriptorRecord>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  30. <EntryVersion>
    Description: Custom short form of a <Term> used for NLM indexing and searching. All upper case.
    Example:
    <EntryVersion>OCCUP MED</EntryVersion>
    Subelement of: <Term>
    Record Type: D, Q
    Repeating element: no
    Required element: no
    MeSH Browser: Entry Version
    ASCII MeSH: DE (DESCRIPTOR ENTRY VERSION); ENTRY (NON-PRINT ENTRY TERM), PRINT ENTRY subelement
    ELHILL MeSH: DE (266); QE (212); BX (277) subelement

  31. <Frequency>
    Description: Number of citations indexed with the SCR in PubMed. Automatically incremented monthly.
    Example:
    <Frequency>1</Frequency>
    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: Frequency
    ASCII MeSH: FR (FREQUENCY)
    ELHILL MeSH: FR (922)

  32. <HeadingMappedTo>
    Description: <DescriptorRecord> or <DescriptorRecord><QualifierRecord> combination, which is to be automatically attached to a citation in PubMed whenever the SCR is used to index the citation. The Descriptor's <RegistryNumber> is also automatically attached unless it is 0.
    Example (from C000011):
    <HeadingMappedTo>
    <DescriptorReferredTo>
    <DescriptorUI>D015125</DescriptorUI>
    <DescriptorName>
    <String>Oxyquinoline</String>
    </DescriptorName>
    </DescriptorReferredTo>
    <QualifierReferredTo>
    <QualifierUI>*Q000031</QualifierUI>
    <QualifierName>
    <String>analogs & derivatives</String>
    </QualifierName>
    </QualifierReferredTo>
    </HeadingMappedTo>
    Subelement of: <HeadingMappedToList>
    Record Type: SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Heading Mapped to
    ASCII MeSH: HM (HEADING MAPPED-TO)
    ELHILL MeSH: HM (291)

  33. <HeadingMappedToList>
    Description: Set of one or more <HeadingMapped> elements.

    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  34. <HistoryNote>
    Description: Free-text giving information deemed helpful to the online searcher. Headings and entry terms are entered in upper case. Initial characters refer to the year in which the record was created in MeSH in its current form (i.e., with the same preferred term). A date in parentheses indicates the oldest creation date of terms, provisional headings (before 1975), or minor headings (before 1991), which are reflected in citations indexed to the record. Entries without a year date are early records, dating between 1963 and 1966.
    Example:
    <HistoryNote>2004 (2002); for SMALL ROUND-STRUCTURED VIRUSES use NORWALK VIRUS 1992-2001</HistoryNote>
    See also <PublicMeSHNote> which was designed for the user of the printed Index Medicus (discontinued 2005) and reflects the MeSH vocabulary printed in Index Medicus at that point in time.

    Subelement of: <DescriptorRecord>;<QualifierRecord>
    Record Type: D, Q
    Repeating element: no
    Required element: no
    MeSH Browser: History Note
    ASCII MeSH: HN (HISTORY NOTE)
    ELHILL MeSH: HN (219) and entry term subelement

  35. <IndexingInformation>
    Description: <DescriptorRecord> or <DescriptorRecord><QualifierRecord> combination which is usually broader than the SCR, and which is suggested for addition to the citation.
    Example (from C000063):
    <IndexingInformation>
       <DescriptorReferredTo>
          <DescriptorUI>D007918</DescriptorUI>
          <DescriptorName>
               <String>Leprosy</String>
           </DescriptorName>
       </DescriptorReferredTo>
       <QualifierReferredTo>
          <QualifierUI>Q000188</QualifierUI>
          <QualifierName>
             <String>drug therapy</String>
          </QualifierName>
       </QualifierReferredTo>
    </IndexingInformation>
    Subelement of: <IndexingInformationList>
    Record Type: SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Indexing Information
    ASCII MeSH: II (INDEXING INFORMATION)
    ELHILL MeSH: II (278)

  36. <IndexingInformationList>
    Description: Set of one or more <IndexingInformation> elements.

    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  37. IsPermutedTermYN
    Description: Attribute of the <Term> element which indicates whether or not the term is created automatically in the MeSH editing application as a variant of another term in the record.
    Example:
    <Term ConceptPreferredTermYN="N"
    IsPermutedTermYN="Y"
    LexicalTag="LAB"
    RecordPreferredTermYN="N">
    <TermUI>T000001</TermUI>
    <String>A 23187</String>
    ...
    </Term>
    Subelement of: not applicable; attribute of <Term>
    Record Type: D, Q, SCR
    Repeating attribute: no
    Required attribute: yes
    MeSH Browser: none
    ASCII MeSH: ENTRY (NON-PRINT ENTRY TERM).
    ELHILL MeSH: BX (277).

  38. LanguageCode
    Description: Attribute of <DescriptorRecordSet> having as values abbreviations for the language of the XML data. For English, the value is 'eng'. Other abbreviations will be used primarily by institutions that translate MeSH into their own language.

    Subelement of: not applicable.
    Attribute of <DescriptorRecordSet>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  39. LexicalTag
    Description: Attribute of the <Term> element, consisting of one of the following lexical categories:
    ValueMeaning
    ABB (Abbreviation)
    ABX (Embedded abbreviation)
    ACR (Acronym)
    ACX (Embedded acronym)
    EPO (Eponym)
    LAB (Lab number)
    NAM (Proper name)
    NON (None)
    TRD (Trade name)

    Example:
    <Term ConceptPreferredTermYN="Y"
    IsPermutedTermYN="N" LexicalTag="LAB"
    RecordPreferredTermYN="N">
    <TermUI>T000001</TermUI>
    <String>A-23187</String>
    ...
    </Term>
    Note that a Permuted Term will always have the same Lexical Tag value as the term from which it is generated. See attribute IsPermutedTermYN.

    Subelement of: not applicable . Attribute of <Term>
    Record Type: D, Q, SCR
    Repeating attribute: no
    Required attribute: yes
    MeSH Browser: Lexical Tag [only in the Descriptor Expanded Concept View]
    ASCII MeSH: ENTRY (NON-PRINT ENTRY TERM), PRINT ENTRY subfield
    ELHILL MeSH: none

  40. <Month>
    Description: Two-character string giving the month of the year. Similar in format to the MEDLINE element of the same name.

    Subelement of: <DateCreated>; <DateRevised>; <DateEstablished>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  41. <NLMClassificationNumber>
    Description: Classification Number provided by the NLM Cataloging and Metadata Management Section (CAMMS).
    Example: <NLMClassificationNumber>WJ 342</NLMClassificationNumber>

    Subelement of: <DescriptorRecord>
    Repeating element: no
    Required element: no
    MeSH Browser: Not Shown
    ASCII MeSH: Not Shown
    ELHILL MeSH: Not Shown
  42. <Note>
    Description: Free-text narrative giving information about the substance particularly its biological properties, but may include other information such as about the <RegistryNumber>. "structure" indicates that the structure of the chemical is given in the first <Source>.
    Example:
    <Note>venous tonic; structure given in first source</Note>
    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: no
    MeSH Browser: Note
    ASCII MeSH: NO (NOTE)
    ELHILL MeSH: NO (211)

  43. <OnlineNote>
    Description: Free-text information formerly intended to help the online searcher. The Online Note is superseded by the <HistoryNote> when the <OnlineNote> is not present.
    Example:
    <OnlineNote>search ALBUMINS 1966-72.</OnlineNote>f
    Subelement of: <DescriptorRecord>
    Record Type: D, Q
    Repeating element: no
    Required element: no
    MeSH Browser: Online Note
    ASCII MeSH: OL (ONLINE NOTE)
    ELHILL MeSH: OL (217)

  44. <PharmacologicalAction>
    Description: Reference to a Descriptor describing observed biological activity of an exogenously administered chemical represented by a Descriptor or SCR.
    Example:
    <PharmacologicalAction>
    <DescriptorReferredTo>
    <DescriptorUI>D000900</DescriptorUI>
    <DescriptorName>
    <String>Antibiotics</String>
    </DescriptorName>
    </DescriptorReferredTo>
    </PharmacologicalAction>
    Subelement of: <PharmacologicalActionList>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Pharm. Action
    ASCII MeSH: PA (PHARMACOLOGICAL ACTION)
    ELHILL MeSH: PA (292)

  45. <PharmacologicalActionList>
    Description: Set of one or more instances of a <PharmacologicalAction > in a Descriptor or SCR.
    Example (Descriptor):
    <DescriptorRecord DescriptorClass = "1">
    <PharmacologicalActionList>
    <PharmacologicalAction>
    ...
    </PharmacologicalAction>
    </PharmacologicalActionList>
    </DescriptorRecord>
    Subelement of: <DescriptorRecord>; <SupplementalRecord>
    Record Type: D, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  46. PreferredConceptYN
    Description: Attribute of the <Concept> element, indicating whether or not the concept is the preferred concept of the record. The preferred concept is the meaning of the term which names the record. The preferred concept is frequently a broader concept that includes narrower sub-concepts, but may also be one among several distinct concepts. In any case the preferred concept is selected as the primary or most prominent representation among the concepts in the literature to be indexed by the record.
    Example:
    <Concept PreferredConceptYN="Y">
    Subelement of: not applicable; attribute of <Concept>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Preferred [only in the two Descriptor Concept views]
    ASCII MeSH: none
    ELHILL MeSH: none

  47. <PreviousIndexing>
    Description: Different usage in Descriptors and SCRs:

    In Descriptors: Free-text field referring to Descriptors or Descriptor/Qualifier combinations which were used to index the concept in the MEDLINE databases before the Descriptor was created. Intended to enable users of new Descriptors to find similar concepts indexed before the Descriptor was created. Includes dates of the format (YYYY) for a single year or (YYYY-YYYY) for a range of years. May include descriptive text referring to a group of Descriptors as "specifics". References are not currently maintained when a <DescriptorName> or <QualifierName> changes.
    Example:
    <PreviousIndexing>Hypertension/complications (1972-1999)</PreviousIndexing>
    Subelement of: <PreviousIndexingList>

    In SCRs: The Descriptors or Descriptor/Qualifier combinations refer to the Heading Mapped to which the NM was previously mapped. Thus the reference often exists concurrently with the SCR, unlike the Descriptor PI, though the PI may also include information on the history of the concept, such as if it was previously a descriptor. Descriptor term is in upper case, unlike the Descriptor PI.
    Example:
    <PreviousIndexing>ASPARTIC ACID/*analogs (75-91)</PreviousIndexing>
    Subelement of: <PreviousIndexingList>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Previous Indexing
    ASCII MeSH: PI (PREVIOUS INDEXING)
    ELHILL MeSH: PI (271)

  48. <PreviousIndexingList>
    Description: Set of one or more <PreviousIndexing> elements in a Descriptor or Supplementary Concept record.

    Subelement of: <DescriptorRecord>
    Record Type: D, SCR
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none
  49. <PublicMeSHNote>
    Description: Free-text information about the history of changes in the record that may be helpful to the user of Index Medicus. This includes the date the record was created in MeSH, changes in the preferred term, earlier status as a <SupplementalRecord>, etc. Unlike the <HistoryNote>, MeSH terms reflect the MeSH vocabulary printed in the Index Medicus (discontinued 2005) at that point in time, not as updated for online databases. In Descriptors, applies only to records having DescriptorClass value of 1. MeSH terms are in upper case.
    Example:
    <PublicMeSHNote>2004; see NORWALK-LIKE VIRUSES 2002-2003; for SMALL ROUND-STRUCTURED VIRUSES
    see NORWALK VIRUS 1992-2001
    </PublicMeSHNote>
    See also <HistoryNote> which is designed for the online searcher.

    Subelement of: <DescriptorRecord>
    Record Type: D, SCR
    Repeating element: no
    Required element: only in records in which <DescriptorClass> has a value of 1.
    MeSH Browser: none
    ASCII MeSH: PM (PUBLIC MESH NOTE)
    ELHILL MeSH: PM (218)
  50. <QualifierName>
    Description: Term that uniquely names its <QualifierRecord> and, along with the <QualifierUI>, is used to represent the Qualifier in other elements. The same term as the preferred <Term> of the preferred <Concept> of the Qualifier record. Comparable to, and the source of, the MEDLINE element of the same name. (Note that the MEDLINE element has different attributes.)
    Example:
    <QualifierName>
    <String>biosynthesis</String>
    </QualifierName>
    Subelement of: <QualifierRecord>; <QualifierReferredTo>.
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Subheading
    ASCII MeSH: SH (SUBHEADING)
    ELHILL MeSH: SH (200)

  51. <QualifierRecord>
    Description: Cluster of one or more concepts used in combination with a <DescriptorRecord> for subject indexing and retrieval. Identified uniquely by a <QualifierUI> and <QualifierName>. A Qualifier. A Qualifier record. Also known as a Subheading.
    Example:
    <QualifierRecord>

    ...

    </QualifierRecord>
    Subelement of: <QualifierRecordSet>
    Record Type: Q
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  52. <QualifierRecordSet>
    Description: The set of all <QualifierRecord> elements in the Qualifier XML file.

    Subelement of: none; this is the root element.
    Record Type: Q
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  53. <QualifierReferredTo>
    Description: The pair of elements <QualifierUI> and <QualifierName> each of which uniquely refers to a <QualifierRecord>, and is used to represent the <QualifierRecord> in other elements.
    <QualifierReferredTo>
    <QualifierUIQ000096</QualifierUI>
    <QualifierName>
    <String>biosynthesis</String>
    </QualifierName>
    </QualifierReferredTo>
    Subelement of: <AllowableQualifier>; <ECIN>; <ECOUT>; <IndexingInformation>; <HeadingMappedTo>.
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none
  54. <QualifierUI>
    Description: Qualifier Unique Identifier. Seven-character alpha-numeric string uniquely identifying a <QualifierRecord> and, along with the <QualifierName>, used to represent the Qualifier record in other elements.
    Example:
    <QualifierUI>Q000002</QualifierUI>
    Subelement of: <QualifierRecord>; <QualifierReferredTo>.
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: Unique ID
    ASCII MeSH: UI (UNIQUE IDENTIFIER)
    ELHILL MeSH: UI (480)


  55. RecordPreferredTermYN
    Description: Attribute of the <Term> element which indicates whether or not the term is the preferred term of the record. See Introduction to MeSH in XML format. Similar to <DescriptorName>, <QualifierName>, <SupplementalRecordName>.


    Example:
    <Term ConceptPreferredTermYN="Y"
    IsPermutedTermYN="N"
    LexicalTag="NON"
    RecordPreferredTermYN="Y">
    <TermUI>T000002</TermUI>
    <String>Calcimycin</String>
    ...
    </Term>
    Subelement of: not applicable; attribute of <Term>
    Record Type: D, Q, SCR
    Repeating attribute: no
    Required attribute: yes
    MeSH Browser: Equivalent to the labels "MeSH Heading", "Subheading", and "Name of Substance".
    ASCII MeSH: equivalent to the labels "MH", "SH", and "NM".
    ELHILL MeSH: equivalent to the labels "MeSH Heading", "Subheading", and "Name of Substance".

  56. <RegistryNumber>
    Description: Originally a Registry Number from CAS (Chemical Abstracts Service) for the same chemical. Compare to, and the source of, the MEDLINE element of the same name. Currently it may be any one of the following:
    1. Enzyme number from the Enzyme Commission.
      Example: EC 2.4.2.17, partial enzyme number: EC 1.4.3.-.
    2. Registry number from Chemical Abstracts Service (CAS). Example: 7004-12-8.
    3. A ten character FDA Substance Registration System Unique Identifier (UNII). Example: R16CO5Y76E.
    4. Value of 0 if no match is available in the above categories.
    Example:
    <RegistryNumber>7004-12-8</RegistryNumber>
    Subelement of: <Concept>
    Record Type: D, SCR
    Repeating element: no
    Required element: In Descriptors having a D category <TreeNumber>.
    MeSH Browser: Registry Number [as concept attribute in the Descriptor Enhanced Concept View]
    ASCII MeSH: RN (CAS REGISTRY/EC NUMBER)
    ELHILL MeSH: RN (261)

  57. <RelatedRegistryNumber>
    Description: The same type of value as the <RegistryNumber> but for concepts which do not have their own Descriptor or Supplemental record. For example, these might be salts and/or stereoisomers of the parent compound. Most values correspond to a <RegistryNumber> value in a sub-concept in the record. A CAS number may be followed by note in parentheses which specifies the chemical relation between the <RelatedRegistryNumber> entry and the concept compound. Example:
    <RelatedRegistryNumber>157810-81-6 (sulfate (1:1) (salt))</RelatedRegistryNumber>
    Subelement of: <RelatedRegistryNumberList>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Related Number
    ASCII MeSH: RR (RELATED REGISTRY NUMBER)
    ELHILL MeSH: RR (610)

  58. <RelatedRegistryNumberList>
    Description: The set of one or more occurrences of the <RelatedRegistryNumber>.

    Subelement of: <Concept>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none
  59. RelationName
    Description: Attribute of the <ConceptRelation> element which indicates the relation between the two concepts, e.g., NRW.

    Subelement of: not applicable; attribute of <ConceptRelation>.
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Narrower, Broader, Narrower [only in the two Descriptor Concept Views.]
    ASCII MeSH: ENTRY (ENTRY TERM) subelement; PRINT ENTRY subelement
    ELHILL MeSH: none

  60. <ScopeNote>
    Description: Free-text narrative giving the scope and meaning of a <Concept>.
    Example (for 'Arthroplasty, Replacement, Hip'):
    <ScopeNote>Replacement of the hip joint</ScopeNote>
    Subelement of: <Concept>
    Record Type: D, Q
    Repeating element: no
    Required element: no
    MeSH Browser: Scope Note [Concept attribute in both Descriptor Concept views]
    ASCII MeSH: MS (MESH SCOPE NOTE)
    ELHILL MeSH: MS (215)

  61. SCRClass
    Description: Attribute of <DescriptorRecord> having as a value one of four numbers:
    • 1 = Regular chemical, drug, or other substance (the most common type)
    • 2 = Protocol, for example, FOLFOXIRI protocol
    • 3 = Rare disease, for example, Canicola fever
    Subelement of: not applicable. Attribute of <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  62. <SeeRelatedDescriptor>
    Description: Reference to a specific Descriptor to which a user is referred by a "see related" cross-reference. For example, in the Descriptor for 'Abdominal Muscles' there is a see-related reference to another Descriptor 'Abdominal Wall'. As in all of XML MeSH, reference to a Descriptor includes the unchanging name - the <DescriptorUI> and <DescriptorName>, as subelements of <DescriptorReferredTo>. Example, in the Descriptor 'Abdominal Muscles':
    <SeeRelatedDescriptor>
    <DescriptorReferredTo>
    <DescriptorUI>D034861</DescriptorUI>
    <DescriptorName>
    <String>Abdominal Wall</String>
    </DescriptorName>
    </DescriptorReferredTo>
    </SeeRelatedDescriptor>
    Subelement of: <SeeRelatedList>
    Record Type: D
    Repeating element: yes
    Required element: no
    MeSH Browser: See Also
    ASCII MeSH: FX (FORWARD CROSS REFERENCE (SEE ALSO REFERENCE))
    ELHILL MeSH: FX (262) and entry term subelement

  63. <SeeRelatedList>
    Description: Set of one or more <SeeRelatedDescriptor> elements in a Descriptor record.

    Subelement of: <DescriptorRecord>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none
  64. <SortVersion>
    Description: Custom version of a <Term> that was used to sort print output in printed Medical Subject Headings (discontinued 2007) when sorting according to the <Term> is not desired. All upper case.
    Example:
    <SortVersion>KETOACYL COA THIOLASE 03</SortVersion>
    Subelement of: <Term>
    Record Type: D, Q
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: DS (DESCRIPTOR SORT VERSION); PRINT ENTRY (ENTRY TERM, PRINT) subelement
    ELHILL MeSH: DS (269); QS (213), BX (277) subelement

  65. <Source>
    Description: Citation reference in which the indexing concept was first found. Single occurrence since 1980.
    Example:
    <Source>S Afr Med J 50(1):4;1976</Source>
    Subelement of: <SourceList>
    Record Type: SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: Source
    ASCII MeSH: SO (SOURCE)
    ELHILL MeSH: SO (602)

  66. <SourceList>
    Description: Set of one or more <Source> elements.

    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  67. <String>
    Description: The string itself that constitutes a <Term> as well as object names, such as the <DescriptorName>. There is exactly one <String> for every <Term>. One difference between the <String> and <Term> is that the <Term> is the bearer of a term's attributes, such as Lexical Tag.
    Example:
    <Term ConceptPreferredTermYN="Y"
    IsPermutedTermYN="N"
    LexicalTag="NON"
    RecordPreferredTermYN="Y">
    <TermUI>T000002</TermUI>
    <String>Calcimycin</String>
    ...

    </Term>
    Subelement of: <Term>; <DescriptorName>; <QualifierName>; <ConceptName>; <SupplementalRecordName>.
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  68. <SupplementalRecord>
    Description: Cluster of one or more concepts used for subject indexing and retrieval. Identified uniquely by a <SupplementalRecordUI> and <SupplementalRecordName>. SCR. Supplemental Record. Formerly known as Supplementary Chemical Records.
    Example:
    <SupplementalRecord>
    ...
    </SupplementalRecord>
    Subelement of: <SupplementalRecordSet>
    Record Type: SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  69. <SupplementalRecordName>
    Description: A term that uniquely names its <SupplementalRecord> (SCR) and, along with the <SupplementalRecordUI>, is used to represent the SCR. The same term as the preferred <Term> of the preferred <Concept>. Comparable to, and the source of, the <NameOfSubstance> element in MEDLINE.

    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Example:
    <SupplementalName>
    <String>bevonium</String>
    </SupplementalName>
    Repeating element: yes
    Required element: yes
    MeSH Browser: Name of Substance
    ASCII MeSH: NM (NAME OF SUBSTANCE)
    ELHILL MeSH: NM (290) , SY (616)

  70. <SupplementalRecordSet>
    Description: The set of all <SupplementalRecord> elements in the SCR XML file.
    Subelement of: none; this is the root element.
    Record Type: SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  71. <SupplementalRecordUI>
    Description: Unique Identifier for SCRs. Seven-character alpha-numeric string uniquely identifying a <SupplementalRecord> and, along with the <SupplementalRecordName>, is used to represent the SCR in other elements.
    Example:
    <SupplementalRecordUI>C000002</SupplementalRecordUI>
    Subelement of: <SupplementalRecord>
    Record Type: SCR
    Repeating element: no
    Required element: yes
    MeSH Browser: Unique ID
    ASCII MeSH: UI
    ELHILL MeSH: UI (480)

  72. <Term>
    Description: Alpha-numeric string which comprises the basic unit of the MeSH vocabulary. Also functions as the name of a Descriptor and concept. The term itself is the <String> element. Every Term has five XML attributes:


    Example:
    <Term ConceptPreferredTermYN="Y"
    IsPermutedTermYN="N"
    LexicalTag="NON"
    RecordPreferredTermYN="Y">
    <TermUI>T000002</TermUI>
    <String>Calcimycin</String>
    <DateCreated>
    <Year>1999</Year>
    <Month>01</Month>
    <Day>01</Day>
    </DateCreated>
    <ThesaurusIDlist>
    <ThesaurusID>NLM (1975)</ThesaurusID>
    </ThesaurusIDlist>
    </Term>
    Subelement of: <TermList>
    Repeating element: yes
    Required element: yes
    MeSH Browser: MeSH Heading; Entry Term; Name of Substance; Subheading;
    Term [in both Descriptor Concept views]
    ASCII MeSH: MH, ENTRY, SH, QX; NM, SY
    ELHILL MeSH: MH (251), BX (277) ; SH (200), QX(223); NM (290), SY (616)

  73. <TermList>
    Description: Set of one or more <Term> elements in a <Concept>.
    Subelement of: <Concept>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  74. <TermNote> (Term Note)
    Description: For institutions that translate MeSH into their own language. Internal notes about a given term for future reference by the translators. Free text format.
    Subelement of: <Term>
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  75. <TermUI> (Term Unique Identifier)
    Description: Seven-character alpha-numeric string uniquely identifying a <Term> (except automatically generated Permuted Terms; see attribute IsPermutedTermYN).
    Example:
    <TermUI>T000003</TermUI>
    Subelement of: <Term>
    Repeating element: yes
    Required element: yes
    MeSH Browser: Term UI [only in Descriptor Expanded View.]
    ASCII MeSH: none
    ELHILL MeSH: none

  76. <ThesaurusID>
    Description: Name of a Thesaurus in which the terms occurs, including NLM (=MeSH).
    Example:
    <ThesaurusID>BIOETHICS (1991)</ThesaurusID>
    Subelement of: <ThesaurusIDlist>
    Repeating element: yes
    Required element: no
    MeSH Browser: Thesaurus [only in Descriptor Expanded View.]
    ASCII MeSH: MH_TH (THESAURUS ID); ENTRY (NON-PRINT ENTRY TERM), PRINT ENTRY subfield
    ELHILL MeSH: MHTH (321); TH (276), BXTH (701)

  77. <ThesaurusIDList>
    Description: Set of one or more <ThesaurusID> elements in a Descriptor or SCR <Term>.
    Subelement of: <Term>
    Record Type: D, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  78. <TranslatorsEnglishScopeNote>
    Description: For institutions that translate MeSH into their own language. The translator's English scope note for a new concept which the translators themselves have introduced.
    Subelement of: <Concept>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  79. <TranslatorsScopeNote>
    Description: For institutions that translate MeSH into their own language. Translation of an existing <ScopeNote> into a non-English translator's language. It is also used for new concepts introduced by translators in their own language.
    Subelement of: <Concept>
    Record Type: D
    Repeating element: no
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  80. <TreeNumber>
    Description: Alpha-numeric string referring to location within a Descriptor or Qualifier hierarchy. Used for browsing the MeSH vocabulary and for inclusive searches by retrieval systems using MeSH. (Note that the Trees hierarchy is not represented in XML by using subelements. The hierarchy is represented by the Tree Number itself.)
    Example:
    <TreeNumber>C02.839.040</TreeNumber>
    Subelement of: <TreeNumberList>
    Record Type: D, Q
    Repeating element: yes
    Required element: yes
    MeSH Browser: Tree Number
    ASCII MeSH: MN (MESH TREE NUMBER)
    ELHILL MeSH: MN (273)

  81. <TreeNumberList> Description: Set of one or more <TreeNumber> elements in a Descriptor or Qualifier record.
    Subelement of: <DescriptorRecord >; <QualifierRecord>
    Record Type: D, SCR
    Repeating element: yes
    Required element: yes
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none

  82. <Year>
    Description: Four-character year date in YYYY format. Similar in format to the MEDLINE element of the same name.
    Subelement of: <DateCreated>; <DateRevised>; <DateEstablished>
    Record Type: D, Q, SCR
    Repeating element: yes
    Required element: no
    MeSH Browser: none
    ASCII MeSH: none
    ELHILL MeSH: none