journal-id-type Type of Journal Identifier

Type of journal identifier or the authority that created a particular journal identifier.
OPTIONAL on elements: <journal-id>, <related-article>
Value Meaning
Text, numbers, or special characters Word or phrase that identifies the organization or service who assigned the identifier (for example, “index” to indicate an abstracting or indexing service) or names the type of identifier (for example, “doi”).
Restriction @journal-id-type is an optional attribute; there is no default.

Suggested usage

Although designed to accept any text as its value, the following are suggested journal identifier types for this attribute:
Identifier assigned by an archive or other repository
Identifier assigned by a data aggregator
Directory of Open Access Journals
Digital Object Identifier for the entire journal, not just for the article (rare)
Identifier assigned by an abstracting or indexing service
International Standard Serial Number for a journal (This value is generally used when referring to related articles.)
Title abbreviation assigned as identifier by PubMed, for example, “Mol Biol Cell”, “Nucleic Acids Res”, etc. This value is typically an abbreviation for the journal title.
Identifier assigned by PubMed Central, for example, a PubMed Central journal abbreviation such as “pnas”, “mbc”, “nar”, or “molcellb”, etc. This value is typically an abbreviation for the journal title.
Identifier assigned by the content publisher, for example, “MOLEC” or “MOLCEL
Tagged Sample

To indicate PubMed Central assigned the accompanying journal identifier (a PubMed Central journal abbreviation)

<journal-id journal-id-type="pmc">pnas</journal-id>