IACUC Alternatives Searching

MeSH is an accronym for medical subject headings. It is the standardized vocabulary for the Medline database, this means each article that is indexed by Medline is given 10-20 MeSH terms based on the content of the article. MeSH is thus a very powerful tool to be aware of and incorporate into developed search strategies. Medline is freely searchable via the PubMed database, but the Medline content and indexing is also available through paid subscription databases like Ovid, Web of Science and Ebsco. The PubMed platform will offer results in addition to just those that fall under the Medline content.

Test out adding some or all of these terms into your search string to see if improves the precision of your search.

Here is an example of MeSH terms added to the sample search from the previous page:

(Rabbit* OR "Oryctolagus cuniculus" OR "O. cuniculus") AND (Urine OR "Urine collect*") AND (alternative* OR method* OR "reduce stress" OR "stress reduction" OR "metabolism cage*" OR housing OR "Animals, Laboratory"[MeSH] OR "Animal Testing Alternatives"[MeSH] OR "Animal Use Alternatives"[MeSH] OR "Animal Welfare"[MeSH] OR "Housing, Animal"[MeSH])

Automatic term mapping is a function in PubMed wherein your search is automatically interpreted to include MeSH terms and other forms of the terms typed into the search field. At times this can be a helpful feature, but occasionally, it misinterprets your search and you'll want to turn it off because it's returning far too many results.

Example:

If I search the term, nursing, intending to get results about nursing as a profession. The search actually retrieves articles about breastfeeding.

Nursing - 866,185 results - March 21, 2022

Let's take a look at what is actually being searched in the background thanks to automatic term mapping.

"nursing"[MeSH Terms] OR "nursing"[All Fields] OR "nursings"[All Fields] OR "nursing"[MeSH Subheading] OR "breast feeding"[MeSH Terms] OR ("breast"[All Fields] AND "feeding"[All Fields]) OR "breast feeding"[All Fields] OR "nursing s"[All Fields]

The feature attempts to include terms that it pulls automatically from MeSH and transform the terms into plural, and other variations on the term.

To turn off automatic term mapping:

• Use the quotations around a search term. Example: "nursing"
• Use a particular tag at the end of a search term. Example: nursing[tiab]

The fields in PubMed are another important topic to be aware of when building a search using the database. If you don't include any fields or quotation marks around search terms, automatic term mapping will be applied to your search. If you place your search term in quotes, all fields will be searched for matching language. If you place a field tag in square brackets after your search term, it will only search in that field and not others. There are of course many more field tags than those included in the table below, but these might be the most useful in building an alternatives search.

Example search using appropriate field tags:

(Rabbit*[TIAB] OR rabbits[MeSH] OR "Oryctolagus cuniculus"[TIAB] OR "O. cuniculus"[TIAB]) AND (Urine[TIAB] OR "Urine collect*"[TIAB] OR "urine specimen collection"[MeSH]) AND (alternative*[TIAB] OR method*[TIAB] OR "reduce stress"[TIAB] OR "stress reduction"[TIAB] OR "metabolism cage*"[TIAB] OR housing[TIAB] OR "Animals, Laboratory"[MeSH] OR "Animal Testing Alternatives"[MeSH] OR "Animal Use Alternatives"[MeSH] OR "Animal Welfare"[MeSH] OR "Housing, Animal"[MeSH])

Why use MeSH terms and TIAB?

Not all articles within PubMed are Medline articles. In order to be thorough, it's best practice to search both, if you are incorporating field tags into your search. Additionally, it takes time for new articles to be added to the MeSH vocabulary. So a topically relevant article that is present in PubMed now may not have the MeSH tags associated yet, but in a month or two they might be added.