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Research Tips: Boolean

Why Use Boolean?

Boolean can connect search terms together in a way that the database understands what you're searching for.

Learn More:


The AND operator:

  • Use to connect different concepts
  • Requires all of the search terms to appear in the records you retrieve. 
  • Limits your search. The more concepts that you AND together, the smaller the search results.


obesity AND soft drinks


The OR operator:

  • Use to join synonyms or related terms
  • Instructs the database to retrieve any record that contains either (or all) of the terms.
  • Expands your search. The more terms that you OR together the more records you will retrieve.



soda pop OR soft drinks



The NOT operator:

  • excludes results with that keyword
  • reduces results


soft drinks NOT sports drinks


WARNING:  Use NOT with caution. It could remove relevant results that discuss both the topics- soft drinks and sports drinks.


How to Use Boolean Terms in your Search

AND - Use to combine concepts 

  • Type in one concept per search box.
  • Use AND between the search boxes. The database will find articles that cover both concepts.



OR  - use with synonyms or related words

  • Type in one keyword per search box.
  • Use OR between the search boxes. The database will find articles that cover either keyword.