Library Research Skills: Periodical Databases: Tips for searching

Another important concept to understand before you begin searching is Boolean operators, or connectors.  These are three simple words that instruct the database how your keywords should be connected to each other.

AND: When "and" is placed between words, all those words must be present in all of the articles that are retrieved. "And" is always used between different concepts.  For example, "addiction AND violence," "depression AND treatment." Using "and" reduces the number of articles retrieved.

OR: When "or" is placed between words, any of the words can be present in the retreived articles.  Using "or" will usually increase the number of articles retrieved.  NOTE: "or" is always used between similar words in order to capture articles that may use different terminology.  For example: "children OR toddlers," "teenager OR adolescent."

NOT: When "not" is used, any articles that contain that word are excluded from the search result. This operator is not used as frequently as AND and OR.  This too will decrease the number of articles retrieved.

See the diagrams below for a visual representation of how Boolean operators work.

Truncate means to cut something off, or cut short. 

When using a database, truncation can be a great searching tool that allows you to search terms without having to use many OR operators.

For example, you could search "teen OR teens OR teenager OR teenagers."  But it would be much easier to just tell the database to retrieve any article that has a word that begins with "t-e-e-n."  

Use the truncation symbol * attached to the last letter of the word you're truncating.  Entering teen* in the search box will then retrieve all articles that have a word that begins t-e-e-n but has any variant ending after that.   

See the diagram below for more information.