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*Evidence-Based Medicine Resources

This guide focused on the "acquire" stage of evidence-based medicine and the resources and search strategies to support this process.

Searchable Question

Based on the clinical scenario above:

P: bad breath, male, adult

I: tooth-brushing

C: doing nothing

O: reduction in bad breath

Not all of these terms will be used directly in the search, but it's good to be aware of all potential search terms.


Here's the question that you'd base your search on:

Does tooth-brushing, in comparison with doing nothing [i.e., what the patient is currently doing], decrease bad breath in older male adults?

Boolean Operators

Boolean Connector Purpose

AND

Connects different concepts (keywords).

Narrows down the number of results.

OR

Connects synonyms.

Expands the number of results.

NOT

Excludes a concept.

Use with extreme caution (even librarians don't use this one much).

Boolean Examples

These are some examples of how each type of Boolean operator looks when used with keywords:

OR: Connects Similar Concepts 

It expands the number of results on the topic.

Examples Topics of Interest  Search terms connected by OR
College Students college OR university OR higher education OR undergraduate OR post secondary
Racism racism OR racial bias OR prejudice OR systemic racism OR racist
online courses online education OR online learning OR online teaching 
learning communities community OR engagement OR connection OR presence

 

AND: Connects Different Concepts

It narrows down the number of results.

Example Topics of Interest Search terms connected by AND
College students experiences of racism.

college OR university OR higher education OR undergraduate OR post secondary

AND

racism OR racial bias OR prejudice OR systemic racism OR racist

The role of engagement in successful online courses.

community OR engagement OR connection OR presence

AND

online education OR online learning OR online teaching 

 

NOT: Excludes a Concept 

Use with extreme caution.

Example Topic of Interest Search terms connected by NOT
Quitting tobacco, but just smokeless tobacco (eg vaping). Tobacco cessation NOT smoking
Cloning, but excluding sheep. Cloning NOT sheep

 

Putting It All Together

Here are the terms (also known as a "search string") that will be used to search the database:

(bad breath OR halitosis) AND (toothbrushing OR oral hygiene)

Bad breath & halitosis are synonyms for one concept, so they're connected by OR & placed within parentheses.

Toothbrushing & oral hygiene are synonyms for the second concept. They're connected to the first concept with AND.

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