Automatic Term Mapping is one of the algorithms applied to searches. If field tags, phrase search (double quotation marks or hyphen) or wildcard/truncation (*) are not being used, ATM compares terms against a series of tables (including MeSH) to find related terms and expand your search. Some of the most common tables include:
- Medical Subject Headings (MeSH): Ex. searching for Acid Reflux, PubMed will add "gastroesophageal reflux"[MeSH Terms]
- Journal titles (Name, abbreviations and ISSN): Ex. Searching for BMJ, PubMed will add "British Medical Journal"
- Spellings variations Ex. British and American spelling
- Drug names (brand name - generic name)
- Pairs (singular - plural, known synonyms, closely related words)
- and more
Ex. a search for 'Acid reflux' actually searches: "gastroesophageal reflux"[MeSH Terms] OR ("gastroesophageal"[All Fields] AND "reflux"[All Fields]) OR "gastroesophageal reflux"[All Fields] OR ("acid"[All Fields] AND "reflux"[All Fields]) OR "acid reflux"[All Fields]
More about Automatic Term Mapping.