Search Operators: Boolean Operators

There are 3 Boolean operators used in virtually every database search: AND, OR, and NOT. We write them in all capital letters to let the database know that they are operators, not search terms.

Cecelia Vetter, CC BY-SA 4.0, via Wikimedia Commons

children AND adolescents

• Will return results that contain BOTH the term children and adolescents
• Use this to tie your main terms together

therapy OR treatment

• Will return results that contain EITHER the term therapy, treatment, or both terms.
• Use to tie your synonyms, related terms, and alternate spellings together

Pets NOT cats

• Will return results that contain the word pets, and DO NOT contain the word cats
• Use this to filter out irrelevant results