Changes in PT and MH Tags

This page describes a new XML file for citation maintenance information. For 2007 MEDLINE citations having eight MeSH Category V Descriptors, formerly indexed with the MH tag, are now indexed with the PT tag. The Descriptors are:

Comparative Study
English Abstract
In Vitro
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Research Support, N.I.H., Intramural
Research Support, N.I.H., Extramural

See also the article MeSH® Category V Terms ... NLM Technical Bulletin, September-October, 2006.

While not a change in MeSH data, the change in tags falls within the broader scope of GCM data, which is to make available the annual changes which are made by NLM in the MeSH indexing of citations in PubMed and distributed MEDLINE. Therefore, we are providing these changes in XML format.

Note, however, that this type of change is not routine. There may or may not be similar changes in the future.

Like the existing GCM XML, maintenance data involve "tasks" - specific database transactions, which add, delete, or replace some MEDLINE data. See Citation Maintenance tasks in XML format. The XML format is also similar but does include two additional elements and an additional attribute, so the DTD is different. The following table lists all the elements in the GCM_PT2007.XML file, with the elements new to the file indicated with an asterisk (*).

GCM_PT2007.XML

Element/attribute	Value Range	Description
CitMaintTaskSet		Set of all tasks. Root element.
CitMaintTask		Specific task to replace, add, or delete indexing data.
/Action	Replace, Add, Delete	Nature of the change to the citation.
/TaskSourceType	Manual, Automatic, PrefTerm	Process by which task was created.
MTaskID	M..., A...., P....	Unique identifier for the task. Leading alphabetic, remainder numeric.
MeSHYear	(YYYY)	Year when annual MeSH changes first appear in January.
ExistingMeSHUI	D......, C......, Q......	UI of the MeSH record reference being replaced or deleted. Null when Action is Add. Same value as NewMeSHUI for PrefTterm change.
NewMeSHUI	D......, C......, Q.....	UI of the MeSH record reference replacing the old value, or being added. Null when Action is Delete. Same value as ExistingMeSHUI when only preferred term being changed. May include attached Qualifier UI.
ExistingMeSHPrefTerm	(string)	Preferred term for ExistingMeSHUI.
NewMeSHPrefTerm	(string)	Preferred term for NewMeSHUI.
ExistingMeSHRecType	DESCRIPTOR, SCR, QUALIFIER
NewMeSHRecType	DESCRIPTOR, SCR, QUALIFIER
MajorTopicYN	Y, N	New value may be marked as the major topic of the citation.
ExistingCitationField *	MH, PT	Citation tag to be replaced.
NewCitationField *	MH, PT	Citation tag to replace the old tag.
Sequence	(positive integer)	Order in which tasks must be run.

* Only in the GCM_PT.DTD

Alphabetic List of XML elements different from GCM.XML

The following are the elements in the two XML files. For the complete list see Citation Maintenance tasks in XML format.

<ExistingCitationField>
Description: The MEDLINE citation tag which is being replaced. To date, only the 'MH' tag has been used as a value for this element.
Example:

  <ExistingCitationField>MH</ExistingCitationField>

Subelement of: <CitMaintTask>
In file: GCM.XML, GCM_PT.XML
Required element: no

<NewCitationField>
Description: The MEDLINE citation tag which is replacing an existing tag. To date, only the 'PT' tag has been used as a value for this element.
Example:

   <NewCitationField>PT</NewCitationField>

Subelement of: <CitMaintTask>
In file: GCM.XML, GCM_PT.XML.
Required element: no

TaskSourceType
Description: Process by which task was created. One of the following: PrefTerm, Automatic, Manual, CitationFieldChange.
Example:

   <CitMaintTask Action="Replace" TaskSourceType="CitationFieldChange">

Subelement of: n/a; attribute of <CitMaintTask>
In file: GCM.XML,GCM_PT.XML
Required element: yes

Last reviewed: 21 December 2006
Last updated: 21 December 2006
First published: 20 December 2006
Metadata| Permanence level: Permanent: Dynamic Content