@kwd-group-type
Keyword Authority
This attribute is used with two different definitions:
The most common is the name of the thesaurus, ontology, or organization that established a particular group of keywords, for example, “MESH”, “ISO-463”, “IEEE”, “author-generated”, “ICD9-codes”, etc.
The second usage describes the type of keyword
for some of the more unusual keyword groups (for
example, “hierarchical”
for keywords that
are grouped into a hierarchy,
“abbreviations” for
keywords that contain an abbreviation and its expansion,
or “code” for
keywords that contain a code
and its text but where the source of the codes is unknown).