Connecting Search Terms
Most databases use Boolean Operators to connect different search terms together.
The Boolean Operators
| AND | OR | NOT |
|---|---|---|
| Make search narrower | Make search broader | Make search narrower |
| Connect together two different concepts | Connect alternate terms for the same concept | Remove search terms |
How Library Stuff Works: Boolean Operators (AND OR NOT) - 4 min
This short video from McMaster Libraries gives an excellent overview of Boolean Operators.
How Library Stuff Works: Boolean Modifiers " " , *, ( ) - 3.5 min
This short video from McMaster Libraries gives an excellent overview of other modifiers that are useful for making your searches better, including quotation marks and truncation.
Boolean Operators generally need to be used with parenthesis, like the order of operations in math.
Example by hand:
(post menopause OR post menopausal OR postmenopause OR postmenopausal)
AND
(hormone replacement therapy OR HRT OR menopausal hormone therapy OR MHT)
AND
(breast cancer OR breast carcinoma OR breast tumors OR breast neoplasm OR mammary cancer)
Example using CINAHL advanced search builder:
Many databases, including PubMed and CINAHL, will help do this for you if you use their advanced search builder.
