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Database Searching - Health: Build the Search

Guide for Database Searching for the Health Sciences

Understanding AND/OR in a search

"Venn Diagram for Boolean Operator AND" by ramaxeymiles is licensed under CC BY 2.0"Venn Diagram for Boolean Operator OR" by ramaxeymiles is licensed under CC BY 2.0











"Venn Diagram for Boolean Operator OR" by ramaxeymiles is licensed under CC BY 2.0

"Venn Diagram for Boolean Operator AND" by ramaxeymiles is licensed under CC BY 2.0



Searches for each term separately

Searches for all terms in a single article

Expands the search

Narrows the search

More results

Fewer results

Used between synonyms

Used between concept groups

Surround each group with ( )

No special punctuation


For Example:

(seniors OR senior OR elderly OR elder OR aged OR old OR older) AND ("covid 19" OR covid-19 OR coronavirus OR "sars cov 2" OR sars-cov-2 OR "severe acute respiratory syndrome") AND ("mental health" OR anxiety OR anxieties OR depression OR depressive OR stress OR stresses OR stressing OR lonely OR loneliness OR isolate OR isolated OR isolation)

* note that each grouping of OR words is enclosed in (parentheses)

** note that phrases are enclosed in "quotation marks"

If we insert more terms in each OR grouping, we will get more results.

If we add another concept, like a gender or ethnicity, we will get fewer results.