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STANDARD - tuned to be the most useful search for general concept browsing. The background algorithm is complex and out-of-scope to fully document here. By default, this is configured to find only “active” concepts.
EXACT - this is does a more-or-less “exact-ish” search (when not normalizing for whitespace, some stop words, and punctuation)
NGRAM - useful for when you’re not sure of the spelling of something, or not sure whether the terminology uses noun-like or adjective-like language to label concepts (e.g. “cervical” vs “cervix”).
SNOMED - this only shows when browsing SNOMED terminologies and is a pass-through to the search API of the SNOMED International browser at browser.ihtstdotools.org. It can be used to return concepts in the same way that browser would.
If you encounter unexpected search results under certain circumstances, let us know! We’re always looking to refine and improve the searching algorithms and understand different use-cases require different approaches.
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