Include Sub-terms/Derivatives (explosion search)

If an term has any more specific, or narrower, index terms within the Emtree thesaurus, they are also automatically retrieved as part of the search.  They are all searched together with a Boolean OR operation.

Example:

Within Emtree, heart infarction has several narrower terms: acute heart infarction, Dressler syndrome, heart muscle necrosis, heart right ventrical infarction, silent myocardial infarction, etc.  These are all picked up with an "explosion"? of the thesaurus tree for this term.

See Browse by Facet within Emtree to view term hierarchies and discover what narrower sub-terms can be captured with explosion searches.