UPDATE: “Apply equivalent subjects” option has been set to default “off” . If you want to use this as part of a Advanced Search, tick the box when setting up the parameters of a search.

As of mid-August, 2019, there has been a change to EBSCOhost search results in databases. They have added “Apply equivalent subjects” to the Search Expanders (under Advanced Search) and set the default to “on” (box ticked).

What this means is that in EBSCOhost databases, if a search term or phrase matches to an equivalent concept within its subjects, that concept will be included in the search as well. For example, in ERIC a search for the phrase “conflict management” also automatically includes the phrase “conflict resolution” – unless the box for “Apply equivalent subjects” is un-ticked first.

However, the “subjects” are not consistent between databases. For example, the above “conflict management” search produces the same results in CINAHL with or without “Apply equivalent subjects” activated. It does not add “conflict resolution“. But a search in CINAHL for “medical device” does bring up different results depending if the “Apply equivalent subjects” box is ticked or not as it will add the subject “Equipment and Supplies” (ERIC returns the same number of results for “medical device” either way).

To add a further wrinkle, some databases will look for plurals & possessives of search terms -even when in a phrase- while others won’t. ERIC does this, CINAHL does not… and this can get very confusing if you start to nest truncation in searches or move between databases expecting that they all act the same way.

Look for the listing of subject headings or Thesaurus in your preferred database (if available) to see what it includes and read the following articles for more info:

Upcoming change to your EBSCOhost search results

Why do truncation (*) searches sometimes return fewer results?

How is relevance ranking determined in EBSCOhost?