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Nursing Resources: A Self-Paced Tutorial and Refresher

An online instructional tool to orient users to the NYU virtual environment: books, databases, articles, more.

1.7 Boolean Operators

Understanding "Boolean" operators is fundamental to database searching!

Boolean logic uses the operators AND and OR to connect search terms when using catalogs, databases, or a web search tool.

For example: a research question with a Problem AND Intervention:

Do exercise programs reduce the incidence of accidental falls in the aged population?

Combine two terms with AND for a preliminary literature search:

  • A simple search on: falls retrieves ALL article citations containing that term.
  • Adding a  search term using AND retrieves citations with BOTH  search terms, e.g.: falls AND exercise
    • Adding additional terms with AND narrows the results. 

OR is used to connect synonyms. A search using OR retrieves citations with ANY of search terms present,
e.g.: (exercise OR physical fitness OR swimming). Notice that synonyms are nested within parentheses.

  • Connecting terms with OR will retrieve more results. (OR retrieves MORE!)

Putting it all together, this search retrieves results with the word falls and any one of the terms nested within parentheses:
falls AND (exercise OR physical fitness OR swimming).

Watch the video below, a PubMed search, that demonstrates Boolean connectors.

PubMed: Falls AND Exercise (2 min)





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