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Nesting

When conducting research, often times your topic will have ideas or concepts that can be expressed multiple ways. For example, teenagers might also be described as adolescents, youth, teens, or young adults. Higher education might also be referred to as post-secondary education, tertiary education, colleges or universities. Online learning might also be referred to as distance learning, virtual learning, e-learning, or even correspondence school.

To retrieve the broadest set of search results, you may include several variations of your search terms using the "nesting" approach. Nesting uses parentheses ( ) to keep concepts that are alike together, and to tell the database to look for search terms in the parentheses first. Nesting also uses the Boolean operator OR to connect like terms and the Boolean operator AND to connect the like terms to the rest of the search. For example, in the nested search below, the database will first find any of the words in parentheses and then look for the second term depression.

(teenager OR teen OR adolescent OR youth OR "young adult") and depression

You may also use nesting when you are interested in two different aspects of a topic. For example, if you were looking for symptoms and treatments for schizophrenia, you might use a search like this:

(symptoms OR treatments) AND schizophrenia

Aside from broadening our search, why is nesting so important? Searches may yield vastly different results if the parentheses are omitted. Let’s take a look at an example with and without nesting to illustrate.

“community college” AND (leadership OR administration)

“community college” AND leadership OR administration


In the first example, a search for “community college” AND (leadership OR administration) will yield records that deal with either community college leadership or community college administration. This is an effective search.

However, in the second example, a search for “community college” AND leadership OR administration (with parenthesis omitted) will yield records that deal with community college leadership, or deal with administration alone. In this example, we see that failure to include the parentheses disconnects the term “administration” from the rest of our search. This is likely to lead to an overwhelming number of irrelevant articles in your search results.

In databases such as Roadrunner and EBSCOhost, which provide drop down boxes containing the Boolean operators AND, OR and NOT, it is easy to inadvertently search without using proper nesting. For example, for the reasons discussed above, you will not want to set up your search like this:



Instead, you will want to use the nesting technique within a single search box, as shown below.

As we see in the example above, we are using nesting alongside the phrase searching technique. Note that you can use nesting with other advanced search techniques to build more complex searches, such as the one shown below.

(alcohol OR drug OR (substance N3 abuse)) AND (teenagers OR adolescents)

It is also important to note that there may be some Library databases where nesting is not possible. We recommend clicking on the database help link (typically located in the upper right corner) to help determine if nesting is appropriate. You may also contact the Library with any questions.

 

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