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IWU OCLS Tutorials: Evidence-Based Toolkit for Nursing - Databases


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OCLS Nursing Databases

For a complete list of nursing databases that are available through OCLS, visit OCLS Nursing databases.




Combining Search Terms to Locate Information (an overview)


Once you choose your database, you will need to combine the search terms you chose using the PICO method. This is often done by selecting matching subject headings in the database and by using AND, OR, and NOT to combine the search terms.

Subject headings are controlled vocabulary created by organizations to give consistency to the way that literature is described. Often, the initial words chosen when constructing a PICO(T) question are simply keywords, which are natural language words and not used consistently by all researchers who produce literature. Whenever possible, locate and use the subject headings within a database in order to search for articles. An example of the difference is:

undefinedIn this example, one researcher may use the term 'childbirth', another researcher uses the term 'birth' and another researcher uses the term 'parturition'. All three researchers are describing the same concept, but using different terms to do so. Within a database, a subject heading of 'Parturition' would have been assigned to all three articles, making all three articles easy to find with the subject heading. Without this subject heading, if you had searched using the keyword 'birth', you probably would have missed the articles in which the researchers had used either 'childbirth' or 'parturition'. 

Using subject headings helps you to retrieve articles that are more relevant to your question, while gathering in articles that keyword searching would have missed.

AND, OR, NOT are used to combine search terms (keywords or subject headings) within a database. 

AND is used when you want an article to contain both (or several) concepts--it tells the database that you only want articles that include all your terms. E.g. [Sutures AND staples AND pain] would only give you articles that discuss all three of those keywords or concepts.

OR is used when you want articles on two different concepts or think more than one keyword or subject heading would be appropriate. E.g. [(Sutures OR staples) AND pain] would give you articles that either discuss just sutures AND pain as well as articles that just discuss staples AND pain. Notice that the words with an OR between them live inside parentheses, which is necessary in order for the database to interpret your search correctly. Keep this in mind when using OR.

NOT is used to exclude concepts from searches, however, using NOT often results in missed articles. One example might be: [sepsis NOT mice], which would eliminate articles on 'sepsis in mice.'





Practice Guidelines in OCLS Databases


In many of the IWU OCLS Nursing databases (MEDLINE, CINAHL, Nursing Resource Center), you can limit your search to just practice guidelines - look for a limiter called "guidelines" or "practice guidelines", often found under "Publication Types".



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