Elements
Elements
These XML elements have specific style rules associated with them. This is not a complete list of XML elements included in the NLM Journal Publishing DTD. For guidance using elements not listed here, consult the Tag Library.
Index of elements
Articles may contain more than one abstract. For each abstract beyond the first, specify the attribute @abstract-type.
Sections within abstracts must have either a <title> or a <label>. If neither exists, do not use <sec>. Do not use @sec-type on <sec> within abstracts.
Only set a <title> if it is something other than “Abstract”.
Capture only the abstract in this tag. Other metadata like copyright information, citation information, and keywords are not part of the abstract.
Use the <trans-abstract> element to tag abstracts in languages different from that of the primary article.
Example: Two abstracts in one article. The first abstract contains multiple sections with titles and no @sec-type. The second abstract contains @abstract-type and no sections. Abstracted from Krieger, et al. PLoS Med 2005 Jul; 2(7): e162.
<abstract>
<sec>
<title>Background</title>
<p>Important controversies exist about the extent to which people's health
status as adults is shaped by their living conditions in early life compared
to adulthood....</p>
</sec>
<sec>
<title>Methods and Findings</title>
<p>Our study employed data from a cross-sectional survey and physical
examinations of twins in a population-based....</p>
</sec>
<sec>
<title>Conclusion</title>
<p>These results provide novel evidence that lifetime socioeconomic position
influences adult health and highlight the utility of studying social plus
biological aspects of twinship.</p>
</sec>
</abstract>
<abstract abstract-type="toc">
<p>Differing socioeconomic positions in adult life are associated with
differences in the health of twins raised together.</p>
</abstract>
Set any label or symbol in the <label> element. Do not create symbols or labels in the XML if they do not exist in the published article. Follow copy for all punctuation.
Tag all non-label content as simple text within the element. Do not tag individual address elements in the affiliation. The only exception is email addresses which should be identified in <email>.
See Author/Affiliation Relationship for information on how authors and affiliations are “linked”.
See Samples 1 and 2 for examples.
2.3
Element exists only in version 3.0.
3.0
<alternatives> may only be contained in the following elements
- <app>
- <array>
- <boxed-text>
- <chem-struct>
- <chem-struct-wrap>
- <disp-formula>
- <disp-quote>
- <element-citation>
- <fig>
- <glossary>
- <inline-supplementary-material>
- <inline-formula>
- <mixed-citation>
- <p>
- <sig>
- <sig-block>
- <supplementary-material>
- <table-wrap>
When alternatives are specified in these elements, PMC will choose the alternative for display based on the following priority (broken down by category).
| Category: | Included elements: | Processing priority: |
|---|---|---|
| Citation elements and paragraphs: | <element-citation> <mixed-citation> <p> | <textual-form> |
| Display text: |
<disp-quote> <boxed-text> |
<textual-form> <graphic> |
|
Formulas and chemical structures: |
<chem-struct> <chem-struct-wrap> <disp-formula> <inline-formula> |
<mml:math> <tex-math> <graphic> |
| Signatures: |
<sig> <sig-block> |
<graphic> <textual-form> |
|
Supplementary material |
<inline-supplementary-material> <supplementary-material> |
<media> <graphic> <table> <textual-form> |
| Appendix | <app> |
<textual-form> <media> |
| Array | <array> |
<tbody> (inside <table>) <preformat> <textual-form> |
| Figures | <fig> |
<media> <graphic> |
| Glossary | <glossary> |
<textual-form> <graphic> |
| Table | <table-wrap> |
<table> <array> <graphic> <preformat> <textual-form> |
If none of these objects exist in the <alternatives> element, the article will fail to pass PMC style. Contact PMC if your data cannot be captured using these combinations.
Some elements must not contain a child of <alternatives> that is the same element as itself. The following are not allowed: array, chem-struct, inline-supplementary-material, supplementary-material
The @article-type attribute is required and must be one of the values listed below. The @article-type attribute is not the value used in generating the categories for the Table of Contents. Those values are specified in <article-categories>.
attributes:
- article-type—Most of the articles should have the value of "research-article". Allowed values are: "abstract", "addendum", "announcement", "article-commentary", "book-review", "books-received", "brief-report", "calendar", "case-report", "correction", "discussion", "editorial", "in-brief", "introduction ", "letter", "meeting-report", "news", "obituary", "oration ", "other", "product-review", "reply", "research-article", "retraction", "review-article". See the Tag Library for descriptions of these values. (#REQUIRED)
- xmlns:mml—Fixed value "http://www.w3.org/1998/Math/MathML"
- xmlns:xlink—Fixed value "http://www.w3.org/1999/xlink"
This is a required element that holds subject and other "sorting" type information about the article. PMC requires that there be a <subj-group> with @subj-group-type="heading" to hold headings used to sort the articles on the TOC.
Required element which must contain exactly one @subj-group-type="heading".
Articles may contain more than one <subj-group> but only one may have @subj-group-type="heading".
Contains any unique identifier assigned to the article, such as pii, doi, or PubMed ID.
Tag only one identifier per <article-id>tag.
See Sample 2 for examples.
attributes:
- pub-id-type—Use the values defined in Tag Library.(#REQUIRED)
Tag all article metadata for each article. All articles must contain <article-categories>, <title-group>, <pub-date>, and <fpage> or <elocation-id>. Articles supplied to PMC as ahead-of-print or online first are not required to have <fpage> or <elocation-id> values, however they must have a unique identifier in <article-id>.
Do not use emphasis tags to mimic formatting.
For product reviews, use the explicit title found on the article. If no explicit title is present, use the title of the first (or only) product being reviewed. See Article Title for examples.
Tag notes directly related to the author(s) in <author-note>. If the information can be captured by the attributes available on <contrib>, do not include it as an author note. Tag correspondence information (beyond a simple corresponding author yes/no; see Author Names) in <corresp>. Set all other author-related footnotes in <fn>. Appropriate @fn-type values include:
| Value | Meaning |
|---|---|
| com | article was communicated by |
| con | article was contributed by |
| current-aff | current affiliation |
| deceased | Person has died since the article was written. |
| equal | contributed equally in the creation of the document |
| present-address | contributor's current address |
See Sample 1 for an example.
Jane Doe and Marcus Dorsey
Please address all correspondence to Jane Doe at author@affiliation.edu.
<contrib-group> <contrib contrib-type="author"> <name><surname>Doe</surname> <given-names>Jane</given-names></name> </contrib> <contrib contrib-type="author"> <name><surname>Doresy</surname> <given-names>Marcus</given-names></name> </contrib> <contrib-group> ... <author-notes> <fn id="FN1"> <p>Please address all correspondence to Dr. Jane Doe at <email>author@affiliation.edu</email>.</p> </fn> </author-notes>
Laura Kelly*, Jeff Beck, Anne Jones
*Corresponding author
<contrib-group> <contrib contrib-type="author" corresp="yes"> <name><surname>Kelly</surname> <given-names>Laura</given-names></name> </contrib> <contrib contrib-type="author"> <name><surname>Beck</surname> <given-names>Jeff</given-names></name> </contrib> <contrib contrib-type="author"> <name><surname>Jones</surname> <given-names>Anne</given-names></name> </contrib> </contrib-group>
carries all of the article body. It allows <p> and all paragraph-level objects and then repeating recursive sections (<sec>).
Use <title> for section titles. Do not just set the section titles in <bold> or other formatting.
Back matter elements, such as <app-group>, <glossary> and <ref-list>, should not appear at the end of <body>.
2.3
Contains a bibliographic description of a work.
<citation> can appear within body or <ref-list>. It should include a citation-type attribute.
See Sample PubMed Central Citations for fully-tagged examples.
3.0
This element does not exist in v3.0. See <element-citation> and <mixed-citation>.
attributes:
- citation-type—The type of work being cited (for example, book or journal).(#REQUIRED)
2.3
This element must link to a <contract-sponsor>.
3.0
This element does not exist in v3.0. See <funding-group>.
attributes:
- rid—Reference to corresponding <contract-sponsor> with the prefix "CS".(#REQUIRED)
- xlink:atts—Do not use.
2.3
Set <contract-sponsor> only once, even if there are multiple grants listed. It must link to at least one <contract-num>.
3.0
This element does not exist in v3.0. See <funding-group>.
attributes:
- id—A target for the corresponding <contract-num> with the prefix "CS".(#REQUIRED)
- xlink:atts—Do not use.
Tag only one contributor per <contrib> element.
Only use the @corresp, @deceased, and @equal-contrib attributes when the article does not have notes conveying the same information.
Whenever possible, tag the contributor’s affiliation inside the <contrib> tag. See Author/Affiliation Relationship for examples.
See Samples 1 and 2 for examples.
attributes:
- contrib-type—Value is usually "author" or "editor". Attribute is required unless <contrib> is a descendant of <collab>.
- corresp—Set as "yes" if the author is listed as the corresponding author.
- deceased—Set as "yes" if the author is indicated to have passed on.
- equal-contrib—Set as "yes" on each author that is indicated to have "contributed equally to this work".
- id—Do not use.
- rid—Do not use.
- xlink:atts—Do not use.
Contains one or more <contrib>
If affiliation information is presented for the entire contributor group, tag the <aff> element inside the <contrib-group>.
See Author/Affiliation Relationships for more information.
See Samples 1 and 2 for examples.
Contains the complete copyright statement as it appears in the source.
The contents will usually be the word "Copyright", a copyright symbol, the copyright year, and the name of the copyright holder. Tag the year of copyright in <copyright-year>, whether or not it appears as part of the <copyright-statement>.
Must be contained in <permissions>.
Set any label or symbol in the <label> element. Do not create symbols or labels in the XML if they do not exist in the published article. Follow copy for all punctuation.
Tag all non-label content as simple text within the element. Do not tag individual address elements in the affiliation. The only exception is email addresses which should be identified in <email>.
2.3
This element does not exist in v2.3. See <citation>.
3.0
Do not include punctuation. Tag reference that require punctuation in the XML with <mixed-citation>. See the citation examples for examples using both <element-citation> and <mixed-citation>.
Tag link information outside of the scope of the article.
attributes:
- ext-link-type—Use the values defined in Tag Library.(#REQUIRED)
- xlink:href—Must identify the external reference.(#REQUIRED)
See Sample 2 for examples.
See Display Object Groups for information on when to use this element.
The first page of the article.
If more than one article shares the same first page, specify @seq. Tag the first article with @seq="a", the second @seq="b", etc. See description of Continuous Makeup Articles.
2.3
Tag all unreferenced, floating figures and tables in this element with @position="float".
3.0
Version 3.0 renamed the element to <floats-group>.
2.3
Element does not exist in 2.3. See <floats-wrap>.
3.0
Tag all unreferenced, floating figures and tables in this element with @position="float".
Tag author footnotes in <author-notes>
Tag footnotes that apply to the article as a whole in <fn-group> in <back>.
Tag table footnotes in <table-wrap-foot>.
attributes:
- id—Use prefix FN for non-table footnotes. Use prefix TFN for table footnotes.(#REQUIRED)
- symbol—Do not use. Capture information in <label>.
<journal-meta> and <article-meta> are required.
Do not use <notes> in the frontmatter.
2.3
This element does not exist in v2.3. See <contract-num>, <contract-sponsor>, <grant-num>, <grant-sponsor>.
3.0
Tag only information about the reported research funding. Do not tag copyright or license information in <funding-group>.
2.3
This element does not exist in v2.3. See <contract-num>, <contract-sponsor>, <grant-num>, <grant-sponsor>.
3.0
Tag the complete funding statement in this element, regardless of whether or not other elements within the <funding-group> duplicate the information. PMC displays the content of <funding-statement> and does not use other funding elements to build display content.
Contains one or more <date> elements.
See Sample 1 for an example.
attributes:
- pub-type—Set as "ppub" for a print ISSN and "epub" for an electronic ISSN. If a journal has both, include two successive <issn> tags.(#REQUIRED)
Tag numeric issues as an integer only. If Roman numerals are used, tag as the Roman numeral only. Do not include the word "issue" in the tag.
Tag "Part" issues as "Pt [integer]". Tag "Supplement" issues as "Suppl [integer]". If the Part or Supplement has no integer, then tag as "Pt" or "Suppl" only.
If there is no issue number, do not tag at all.
Multiple journal-ids may be tagged. Specify type of id in @journal-id-type. If PubMed abbreviation is available, tag with @journal-id-type="nlm-ta".
attributes:
- journal-id-type—(#REQUIRED)
Contains all information about the journal.
Contains label information only (Table 1, Figure 1). Does not include <caption> data, such as <title>.
Do not include emphasis that encompasses the entire contents.
2.3
Contains license information for the article. Do not tag copyright information in the license tag.
Must be contained in <permissions>.
Whenever possible, include a URI to the license description using @xlink:href.
See Sample 1 for an example.
<license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/2.5/"> <p>This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</p> </license>
3.0
Contains license information for the article. Do not tag copyright information in the license tag.
Must be contained in <permissions>.
Whenever possible, include a URI to the license description using @xlink:href.
V3.0 is has replaced <p> with <license-p> in <license>. <license-p> is the full <p> model plus <price>. All style rules are unchanged.
See Sample 1 for an example.
<license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/2.5/"> <license-p>This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p> </license>
<list> may or may not have a title. It must have one <list-item> for each point in the list.
attributes:
- list-type—Allowed values: "order", "bullet", "alpha-lower", "alpha-upper", "roman-lower", "roman-upper", "simple".(#REQUIRED)
- prefix-word—This is for a word that should prefix the generated label in the list, eg. "Step".
The numeric last page of the article. Tag the value even if it is the same as the first page.
2.3
This element does not exist in v2.3. See <citation>.
3.0
Maintain all punctuation from the original copy. Tag a minimum of the following tags if they are part of the original citation: <name> of the author, editor, etc.; <source>; <year>; pagination; DOI.
This is the root element for MathML.
Do not use to tag single characters.
attributes:
- id—(#REQUIRED)
Must be an integer from 1-12.
Tag any month range (January-March) as a <season>.
attributes:
- notes-type—Set as "disclaimer" for article disclaimers. Set as "note-in-proof" for notes in proof.
2.3
This element does not exist in v2.3.
3.0
Used to hold text describing funding used to pay any open access fees associated with the article's publication. Do not include the license text (see <license>).
Tag the citation information of the product as completely as possible. Tag information that cannot be described by elements in a <comment>. Tag associated images (book covers, for example) with <inline-graphic> within product.
See Sample 4 for an example.
Articles cannot have more than one <pub-date> with the same @pub-date-type. Tag only one publication date per <pub-date> element.
Any article with a specified @pub-date-type="collection" must have one <pub-date> with @pub-date-type="epub".
The most common @pub-date-type values are "epub", "ppub", "epub-ppub", "epreprint", and "collection". When an article is published in more than one medium, there will be more than one <pub-date>. The number and types of tagged <pub-date> elements depends on the publication model of the journal.
There are two basic classes of publication: issue-based publication and article-based publication.
- Issue-based publication is when an entire issue is "published" at one time — in print, online, or both. Issue publication dates and article publication dates coincide, so the issue publication date is all that is needed.
- Article-based publication is when articles are "published" individually or in small groups. They may be published in Issues (eg, all of the articles published online in June 2005 are in the "June" issue) which may or may not be printed. Even if the articles are not collected in Issues, they are collected in some way - perhaps by random collection dates, by volume, or by year. This "collection" date usually does not coincide with the article publication date.
Here are several examples of publishing models and their corresponding publication dates.
Print-only Model — This is the traditional print model. Articles are collected by the editor, formed into issues, and published and issue-worth at a time. All articles have the same publication date, which coincides with the Issue cover date. For this model, each article will have <pub-date> with @pub-type="ppub". In this model, the issues may go "online" the same day as the print date or sometime thereafter, but the official publication date is controlled by the Issue cover date.
Print–Online Coincident Model — This is a similar model to the Print-only Model, except there is a little more emphasis on the fact that the online version of the issue is published on the same date. For this model, each article will have <pub-date> with @pub-type="epub-ppub".
Print with Electronic Articles Prepublished Model — In this model, some or all of the articles are published (their official publication date) online before the publication date of the print issue. For this model, each prepublished article will have <pub-date> with @pub-type="epub" to represent its individual online publication date, and every article will have a <pub-date> with @pub-type="ppub" to represent the printed issue date.
Print with Electronic "Preprints" — This is similar to the "Print with Electronic Articles Prepublished Model" where articles from an issue appear online before the publication date of the issue. The difference, however, is that the online versions of the articles are electronic preprints and are not officially published. All of the articles are published on the issue cover date, and they all have the same publication date. For this model, each preprint article will have <pub-date> with @pub-type="epreprint" to represent date it was available online, and every article will have a <pub-date> with @pub-type="ppub" to represent the printed issue date.
Articles Published Online and Collected into Print Issues Model — For this model, each article will have <pub-date> with @pub-type="epub" to represent its individual publication date and a <pub-date> with @pub-type="ppub" to represent publication date of the print issue.
Articles Published Online and Collected into "Issues" Online Model — Issues here do not need to be named "Issue 1", "Issue 2", etc. These are just collections of articles online. The collecting might be done by dates (Months, Quarters, Years) or by Volume. For this model, each article will have <pub-date> with @pub-type="epub" to represent its individual publication date and a <pub-date> with @pub-type="collection" to represent the date of the online collection it belongs in. This date may be a day/month/year, month/year, season/year, or just year.
See Sample 2 for examples.
attributes:
- pub-type—The values depend on the model of publication used. See above for details.(#REQUIRED)
<ref-list> contains a set of references (<ref>). It may or may not have a title.
2.3
<ref> contains a reference of some kind. It will usually contain a single <citation> or <nlm-citation>; however, complex References may contain multiple citations or a combination of text and citations.
See References for details on complex references.
3.0
<ref> contains a reference of some kind. It will usually contain a single <mixed-citation> or <element-citation>; however, complex References may contain multiple citations or a combination of text and citations.
See References for details on complex references.
Use this element's attributes to describe the related article's citation information. When using a DOI as the citation, tag the DOI in @xlink:href and @ext-link-type="doi". May be empty.
See Samples 1and 5 for examples.
attributes:
- related-article-type—Value describes the type of article being pointed to. Only use a value listed in the Tag Library.(#REQUIRED)
- ext-link-type—Required if @xlink:href is specified.
- journal-id-type—Required if @journal-id is specified.
- id—(#REQUIRED)
- page—Include only the first page of the target article.
2.3
This article does not exist in v2.3.
3.0
Use this tag to identify related objects that are not journal articles.
As with <related-object>, use this element's attributes to identify the target object citation. The following objects must always exist together:
- @source-id and @source-id-type
- @document-id and @document-id-type
- @object-id and @object-id-type
Specify the type of target object for the most specific unit. For example, if the related-object is a table in a chapter of a book, the table is the most specific unit so specify @object-type="table". If the related-object is a chapter of a book, the most specific unit is the chapter so the correct attribute is @document-type="chapter".
Tag fully, including metadata. Any <journal-meta> or <article-meta> not explicitly tagged in <front-stub> is inherited from the parent <article>.
See fully-tagged examples in Response and Sub-Article
attributes:
- response-type—Values: reply, discussion, addendum(#REQUIRED)
This is a text element. Values might include "Spring", "Fall-Winter", or month ranges like "Apr-Jun".
Do not include the year in <season>.
All sections must contain <title>, <label>, or both. If it does not have either, do not tag it as a section.
Used to capture signatures. If multiple signatures appear, capture in a single <sig-block>.
Tag fully, including metadata. Any <journal-meta> or <article-meta> not explicitly tagged in <front-stub> is inherited from the parent <article>.
See fully-tagged examples in Meeting Reports/Abstracts and Response and Sub-Article
2.3
This element does not exist in v2.3.
3.0
PMC does not guarantee that the display specified in the attributes will be implemented on the HTML rendering of the article and strongly discourages using this element.
Defines the subjects of an article within <article-categories>. These are often used to indicate the Table of Contents headings for an article.
Do not include any <xref> within <subject>. Any article-level footnotes that must be referenced should be referenced from the <article-title>.
Table should be fully tagged.
See Samples 1and 2 for examples. More fully-tagged tables are available on the DTD website.
attributes:
- frame—Specify as "hsides"
- rules—Specify as "groups"
Contains all parts of a single table.
See Display Object Groups for information on when to use this element.
This holds the <article-title>.
If there is a footnote to the title, put the <xref> (with @ref-type="fn") in the <article-title> or <subtitle> element, and set the <fn> in the <fn-group> in <back>.
If the article is a book review, see <article-title> for special rules.
2.3
This element does not exist in v2.3.
3.0
Only tag elements in a single language in the <trans-title-group>. To tag titles in multiple languages, use one <trans-title-group> per language.
Each element contained within the <trans-title-group> must have a corresponding element in the primary language (do not tag <trans-subtitle> if no <subtitle> exists).
attributes:
- xml:lang—Use two-letter, lower case language codes as described in RFC 4646. Values may be obtained from the IANA Language Subtag Registry: http://www.iana.org/assignments/language-subtag-registry.(#REQUIRED)
Tag numeric volumes as an integer only. If Roman numerals are used, tag as the Roman numeral only. Do not include the word "volume" or any related abbreviation in the tag.
If the citation is part of a special issue with no specified volume (like "Supplement 2005"), tag "Suppl" in volume and "2005" in <year>.
If there is no volume number, do not tag at all.
Used to references to objects within the article. Do not include emphasis or punctuation within the element. Do not tag multiple id values in @rid.
The following are the preferred values for @ref-type.
| Value | Meaning | Prefix | Target Element |
|---|---|---|---|
| app | appendix | APP | <app> |
| author-notes | footnote to author | FN | <fn> |
| bibr | bibliographic reference | R | <ref> |
| boxed-text | textbox or sidebar | BX | <boxed-text> |
| disp-formula | display formula | FD | <disp-formula> |
| fig | figure | F | <fig> |
| fn | footnote | FN | <fn> |
| list | list or list item | L | <list> or <list-item> |
| sec | section | S | <sec> |
| supplementary-material | supplementary content | SD | <supplementary-material> |
| table | table | T | <table-wrap> |
| table-fn | table footnote | TFN | <fn> |
Tag lists of cross references by including one <xref> element for each referenced object.
The changes in education level demonstrate the changing attitudes. 1, 2, 5
<p>The changes in education level demonstrate the changing attitudes.<xref ref-type="bibr" rid="B1">1</xref> <xref ref-type="bibr" rid="B2">2</xref> <xref ref-type="bibr" rid="B5">5</xref></p>
Tag ranges of cross references by including an <xref> for the first item, an en-dash (–), and an <xref> for the last item. PMC will display the range as tagged.
The changes in education level demonstrate the changing attitudes. 1–3
<p>The changes in education level demonstrate the changing attitudes. <xref ref-type="bibr" rid="B1">1</xref>–<xref ref-type="bibr" rid="B 3">3</xref></p>
Set the "linked text" inside of the <xref>. PMC will not generate the content of the link based on the id.
The @ref-type must match the target object in the XML, regardless of the object's label.
Correct:
<xref ref-type="table" rid="T1">Table 1<xref> . . . <table-wrap id="T1"> . . . </table-wrap>
Incorrect:
<xref ref-type="table" rid="T1">Table 1<xref> . . . <fig id="T1"> <label>Table 1</label> </fig>
See Sample 1 for an example.
attributes:
- ref-type—This is the @id of the referenced object.(#REQUIRED)
- rid—see the table above for allowed values and ID/IDREF prefixes.(#REQUIRED)
- id—Do not use.