How do I use Boolean operators within a database search?
The Boolean operators AND, OR and NOT are common across search tools including databases and online search engines; they are used to group search concepts together.
Incorrect use of these operators are the most common cause of errors in searches, from basic formative searches to advanced systematic review searching. Be very careful with your search strings and ensure there are no discrepancies in meanings/definitions in your batches of terms.
Please see our guide Using operators in your search.