The boolean operators AND/OR are the cornerstones of a good search. These commands will allow you to tell the database how to combine words in your search so that synonyms are searched differently than different components. Although there are three boolean operators available, only the first two (AND / OR) are recommended.
OR instructs the database to return any record that uses any word connected by it.
For example, combining the words teen and youth with OR will retrieve any record in the database that uses one of those words. Records retrieved will contain either the word teen or the word youth or both words. It would look like this:
teen OR youth
In the context of a knowledge synthesis, OR is used to combine synonyms and subject headings to make the search more comprehensive.
AND is used to combine different concepts of a question by instructing the database to retrieve all the results that contain each concept connected by it.
For example, combining exercise and youth with AND will return any item in the database that uses both of those words, but not those articles that use only one of those words. Only records containing the words exercise and youth will be retrieved. It looks like this:
exercise AND youth
In the context of a knowledge synthesis, AND is used to combine different concepts to make the search more precise.
When AND is used in combination with OR, you are telling the database to retrieve every item that uses at least one term from each of the components in your search query.
For example, a record that is retrieved in the combination below might use the words youth, sport, & mood.
(youth OR teen) AND (exercise OR sport) AND (emotion OR mood)
NOT will tell the database to exclude results that contain a certain word. While this seems tempting, it can have unintended consequences. For example, if you are looking for research only a pediatric population it may seem like using NOT to exclude adults would be helpful. However, a lot of research about children will mention adults even if adults are not the focus of the research.
pediatric NOT adult
Always consult with a librarian before implementing NOT in your search as it is rarely appropriate for a knowledge synthesis.
Use OR to combine subject headings, keywords, and phrases that represent the same concept.
In an EBSCO database, it looks like this. Lines S1, S2, & S3 are combined with OR to create a new search line, S4, which represents your video gaming concept.
As you create each concept block, you will combine them with AND to tell the database to retrieve articles that contain words or phrases from each of your concepts.
In an EBSCO database, it looks like this. Lines S4, S8, & S11 are combined with AND to create a new search line, S12, which represents all of your concepts combined. Click on image to open in new window for larger view.
