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PubMed Training

Boolean Operators: AND & OR

To search for more than one term at a time, you must use Boolean operators.

The two mostly commonly used operators are AND and OR.

To combine multiple concepts in a single search, use brackets to group concepts together. For example, search for headache AND (aspirin OR acetaminophen), not headache AND aspirin OR acetaminophen

PubMed Advanced Search Builder

To build a search with various concepts using Boolean Operators, click on the Advanced Search link at the top of the page.



Step 1: Type keywords  (one concept at a time)

Step 2: Click ADD



Step 3: Repeat Steps 1 & 2 for each concept

Step 4: Click Search 


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