A phrase search--or an "exact phrase" search--means putting two or more words together and enclosing them with a set of quotation marks, like "treatment effectiveness".
This can be very useful for concepts, names, or organizations that are comprised of more than one word. By enclosing a group of words in quotation marks, you're telling the database to only retrieve results in which those words appear and in that exact order.
A nested search--sometimes referred to as a string search--utilizes parentheses to identify relationships between keywords and dictate the order of how a search should be conducted. The keywords inside the parentheses will be searched first and are typically joined together by the Boolean Operator OR.
This type of search is useful for conducting a more thorough search in the database, particularly when researchers want to link multiple concepts together that could be expressed with different terms, spellings, or acronyms.
For example:
("obsessive compulsive disorder" OR OCD) AND (child* OR adolescents) AND "social stigma"
Compare this same search without parentheses: "obsessive compulsive disorder" OR OCD AND child* OR adolescents AND "social stigma"
Notice how the results from the first search string yielded more precise results, while the latter's was more scattered and unfocused. The use of parentheses grounds the search in logic and has the database search for literature on obsessive compulsive disorder and children first, then social stigma.
In general, it's best to use parentheses when grouping keywords that share similar meanings (synonyms).
Proximity searching allows you to narrow searches by finding keywords that are next to, near, or within a specified from each other. Proximity searches utilize specific operators to determine how close--and in what order--you want the search terms to appear.
Every database uses different proximity search operators. In EBSCOhost, the following proximity search operators are used:
To see which proximity search operators are used by ProQuest, please see their search guide here.