NUR152 - EBP Research Guide

Boolean Operators were developed by George Boole (1815-1864).  They are used in database/the Internet search to filter and improve results. They define the relationships between words and phrases so that your search will be more effective and accurate.

McMaster University Library

• Boolean Search Operators

  • Combine two or more keywords with Boolean Search Operators.

    • AND will narrow down your search: "cross infection" AND prevention

    • OR will broaden your search: "cross infection" OR "hospital acquired infection" 

    • You can combine multiple keywords with multiple Boolean Search Operators: ("cross infection" OR "hospital acquired infection") AND prevention

    • will exclude any other unwanted concepts.

AND

–Narrows search

–Retrieves info containing both A and B

OR

–Broadens search

–Containing either A or B or both

–Suitable for synonyms

NOT

–Narrows search

–Containing A only but not B

Try these advanced search techniques for better results.

• Use quotation marks " " to search for a phrase

       ["breast cancer"] will bring back only results that have the word breast next to the word cancer.             This way you won't get results about breast implant or the other cancer.

• Add an * (Truncation) at the end of a word to search for all possible endings/suffixes

  [nurs*] will search for nurse, nurses, nursing