What is Automatic Term Mapping (ATM)?
Automatic Term Mapping (ATM) is a process that happens in the background of most PubMed searches. The database takes the terms that you have entered into the search box and attempts to interpret them and map them to the appropriate MeSH Terms.
In most everyday or casual searches, the ATM feature will help your search by not requiring you to put as many terms into the search box or build more complex search queries.
However, sometimes the ATM process can go in an unexpected or undesired direction. So it is important to understand roughly how the database is interpreting your search, how to investigate any issues, and how to potentially turn this feature off or otherwise control it.
To learn more about ATM, check out the link below.
Where can I see how my search terms are being mapped?
To see how your terms are being mapped, you can view your Search Details in your Search History.
How do they decide how to map a particular term?
Each time you enter a search term into PubMed, the system checks for that term in what it calls its "Translation Tables". These are just a set tools that map terms to other terms.
There are a number of different ways a term might get mapped, but one of the primary ways is to a particular Subject Heading or MeSH Term. Essentially, the database will try to see if there is an official MeSH Term mapped to the keyword you entered. If it can find a match, then it will search for that MeSH term in addition to the term you entered.
What is an Entry Term?
To complete the process described above, the MeSH Vocabulary uses what it calls Entry Terms. These are terms that MeSH and PubMed have decided are synonyms for a given MeSH term.
For example, heart attack is considered a synonym for Myocardial Infarction and is listed as an Entry Term in the Myocardial Infarction MeSH record.
It is important to note that Entry Terms and Automatic Term Mapping are a one-way process. The Entry Terms will provide "entry" for a particular MeSH Term, but not vice versa.
For example, if you search for heart attack, the system will search for both heart attack OR myocardial infarction. But if you search for myocardial infarction, it will not go back and search all the possible entry terms, such as heart attack.
To learn more about Entry Terms, check out the link below:
How can I turn ATM off if I don't want to use it?
Sometimes you may decide that you do not want PubMed to interpret your search terms. For example, you may find that it is interpreting them incorrectly, or in a way that you did not want or expect. Or, you may be running a more structured search for a project like a systematic or scoping review, where you would likely want to have more control over the search and ensure it is reproducible.
If you do not want PubMed to interpret your search terms, you can turn the ATM feature off by using one of the following methods:
