LibGuides: Database Search Strategies: Phrase searches

Phrases

Most databases allow you to specify that adjacent words be searched as phrases. Using quotation marks around search words is a common way to do phrase searching. By using quotation marks, you are telling the database to only bring back results with the words you typed in exactly the order you typed them. Use phrase searching to keep words together in a search so the database will search the phrase and not the individual words.

Example: "breast cancer" will yield results that contain the exact phrase breast cancer. Without the quotation marks, you will get results that include these terms separately (the database would search breast AND cancer).

Search order

Be aware of the logical order in which words are connected when using Boolean operators:

Search terms combined with AND and OR can be entered in any order to retrieve the same results
The NOT operator excludes the search term directly after it
Databases usually recognize AND as the primary operator, and will connect concepts with AND together first.
When using the AND and OR operators in one search, enclose the OR terms in parentheses to force the computer to search for them first. Example: (symptoms OR treatments) AND diabetes

Boolean Strings

Nesting or String searching is an advanced technique to make searches more specific. This method is useful for:

comprehensive searches
building more complex searches
multi-concept search strings
topics where ideas or concepts can be expressed in multiple ways.

Example: teenagers are also described as adolescents, youth, teens, or young adults.

when you are interested in two different aspects of a topic.

Example: (symptoms OR treatments) AND diabetes

Nesting uses parentheses () to dictate the order in which the Boolean operators will be carried out. Specifically, the search terms within parentheses are required to be searched first.

The most common use of nesting is to add multiple search terms in parentheses using the OR operator and linking those terms with other search terms using AND.

Example: (teenager OR teen OR adolescent OR youth OR "young adult") AND depression

Encasing the OR search string forces the computer to complete the OR search first then move on to the AND search.

Brackets or double parentheses are used to enclose multiple strings to make them a single term.

Example: [(alcohol OR drug*) AND (teenagers OR adolescents)] AND anxiety

It is often easy to do Boolean phrase searching from the Advanced Search menu in a database. Specify that you want your words searched as a phrase by choosing the Boolean phrase option, as in the example below:

The Boolean phrase created by the search engine is shown to the left of your search results.