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Nursing: Evidence-Informed Practice Search Module - Basic

Search operators and parentheses

Boolean operators

OR

  • retrieves records that contain at least one of your search terms
  • e.g., (dog OR canine)

AND

  • retrieves records that include all of your search terms
  • e.g., ultrasound AND tuberculosis

NOT

  • retrieves records that contain your first term but exclude your second term
  • e.g., dementia NOT alzheimer's
  • we do not usually recommend that you use NOT in your searches, as you may exclude relevant results

Note: Capitalize your operators as a matter of practice. In some platforms or search systems, it does not matter whether you enter them in uppercase or lowercase, but others (like PubMed or Google Scholar) require them to be in uppercase to work properly.

Proximity operators

  • Many bibliographic databases also allow use of proximity operators
  • The operator, if available, is dependent on the database and platform being searched
  • e.g., on the Ovid platform, adjn is used: primary adj3 care
  • Please see the database-specific operators and search fields

Parentheses/brackets

Use parentheses to set the order of execution of the Boolean logic. Parentheses work in most but not all systems (e.g., they work on the Ovid, PubMed, EBSCOhost, ProQuest, Scopus, and Web of Science platforms, but they are ignored in Google and Google Scholar)

e.g., (chest OR thorax OR thoracic) AND (imaging OR radiographs OR radiography)

Boolean operators - General tutorial

Boolean operators can be placed between your search terms to narrow or broaden a search, or to exclude search terms.

You will find below a brief video on how to use the Boolean operators:

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