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PNR 120: Clinical Article Review Assignment

2. Search Tips

Narrow SignLibrary databases work by having you search by keywords, instead of full sentences. To search for articles in library databases on different diseases or disorders, try searching for the name of your disease or disorder.

Quotation Marks

If your disease or disorder has more than 1 word, put quotation marks around the name of your disease or disorder in the library database. This will search the name of the disease or disorder as a whole, instead of as individual words.

  • "renal failure"
  • "heart palpitations"
  • "sleep apnea"

Boolean Operators

To search multiple keywords at once, you need to use connector terms, also called Boolean Operators. Using a Boolean Operator will tell the database to connect the terms together in your search.

There are three Boolean Operators:

  • AND: All keywords must appear in your results. AND will narrow down a search.
  • OR: Either of the keywords must appear in the results. OR will give you more results.
  • NOT: Excludes certain keywords from your results. NOT will narrow down a search.

Depending on the database you are using, there may be a place to choose which Boolean Operator you want to use, or you may have to type them in with your keywords.

Click on the below tabs to learn more and see examples of Boolean Operators.


AND is the most common of the Boolean Operators. AND will narrow down your search so you get less results, because it is telling the database that your search results must include every one of your search terms.

When you use AND to combine your keywords, keep in mind that while you will get results that have all of your keywords together, they might not necessarily be next to one another.

  • pneumonia AND children
  • "lung cancer" AND treatment
  • hypertension AND diagnosis


The Boolean Operator OR broadens your search. Remember that in database searching, OR means MORE results. OR tells the database that you want results that mention one or both of your search terms.

OR is a helpful operator to use if you have a search term that has multiple meanings, like ALS OR "Amyotrophic Lateral Sclerosis." You will notice when you do your searching, that some authors might use the term "ALS" and others will use "Amyotrophic Lateral Sclerosis" to mean the exact same thing. OR helps you make sure that you find the most possible articles about your topic.

  • "traumatic brain injury" OR TBI
  • "Lou Gehrig's Disease" OR ALS "Amyotrophic Lateral Sclerosis"
  • Alzheimer's OR dementia


The Boolean Operator NOT helps narrow your search by excluding certain terms from your search. When using NOT, you are telling the database that you want information that is related to the first term, but not the second.

NOT is useful if one of your keywords has multiple meanings that keep giving you irrelevant results. NOT can also help if you want to exclude certain patient types from your search.

  • asthma NOT children
  • "heart attack" NOT women
  • "brain tumor" NOT malignant