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Evidence Based Nursing

Going from PICO question to useful library search terms

Once you have formulated your PICO question, then what do you do with it? You can take the terms and turn them into search phrases to use when searching for evidenced based resources.  

Below is an example of how to change PICO terms (intervention/therapy template) into search terms.


P - hospital acquired infection

I - hand washing

C - No hand washing, masks, other solution

O - reduced infection

Start with the P and I because the results will be broader.  Later, the C and O terms can be added to narrow the results.  It is easier to start with broader results and then narrow them than to try and start of with a very specific and narrow search.

First, try using the words and phrases you used in your PICO question. In the example above, that would mean using hospital acquired infection and hand washing.  To turn them into search phrases, simply put them into quotation marks like this:

"hospital acquired infection"

"hand washing"

Here is what you would put into the search box:  "hospital acquired infection" "hand washing"

If you are having difficulty finding good resources, you can try translating the words and terms you used into terms and words that the database uses.  Doing this will help the results be more accurate.  Here is how to search for terms in CINAHL.  Here is how to search for terms in Medline Complete.  Here is information about MeSH and searching for terms in PubMed.

P - Hospital acquired infection  would become: Cross infection in Medline Complete and CINAHL

I - Hand washing would become: Hand disinfection in Medline Complete; handwashing in CINAHL

So, a search in the library would look like this:

In the large search box on the library's welcome page, type the P and I terms.  If the terms are more than one word each, then put quotation marks around the term so that the search engine knows to look for those words together.

P = "cross infection"

I = handwashing

Type into the search box:  "cross infection" handwashing

And click on Search

Below is an article found with that search.  The highlighted words show where to find the subjects section of an article and that the search terms used are subject headings.

search result example

The C and O terms can also be translated and added to the search if the search needs to be narrowed down.  For this example, the C term of masks is the same as the subject heading word.  The O of reduced infection could be translated into "prevention and control".  That term was found in PubMed under subheadings as well as in the subjects section from the article above.

P = "cross infection"

I = handwashing

C = masks

O = "prevention and control"

A more narrow search would then look like:  

"cross infection" "prevention control" masks handwashing

You could also search for:

"cross infection prevention control" masks handwashing

"cross infection" "prevention control" handwashing

 

MeSH in PubMed.gov

Another place to look for alternate words to try in a search is the MeSH database at http://www.pubmed.gov

MeSH stands for Medical Subject Headings.  In the box for Medline Complete, MeSH 2015 is mentioned. That is the latest version of the subject headings.  The version used in PubMed has more information and ideas for words to try if your search is not bring back what you need.  PubMed can also be a little bit easier to use.

Head over to PubMed.  Under More Resources you will find a link to the MeSH Database.

PubMed example

In the search box, type a term that you would like to find the MeSH heading for and then click on Search.

For this example, cancer was used.

search box

The top item should be the MeSH heading.  Just below the heading will be a brief definition which is helpful to determine that the MeSH heading is what you are looking for.  Click on the heading.

resutls

On the next screen you will see a list of subheadings. These can help to make a search more precise.  For example:

neoplasms epidemiology

neoplasms physiopathology

subheadings

If you scroll down further, you will see what are called Entry Terms.  These are the terms that when typed into the search box will be directed to the MeSH heading record you are looking at.  In this case, instead of typing cancer into the search box, you could have typed tumors or neoplasia and you would have still been directed to neoplasms.  This can be helpful when searching as well.  These terms could be used as alternatives to cancer or neoplasm and could also be combined with the subheadings above.

tumor physiopathology

neoplasia epidemiology

 

Finding CINAHL terms

On CINAHL's advanced search page (library.purdueglobal.edu/cinahl), you will see CINAHL Headings located just above the search boxes.  Click on CINAHL Headings

CINAHL headings

In the search box on the next screen, type your term. For this example, hospital acquired infection was used.

Click on Browse

There is also a link to View Tutorials if you would like additional training.

tutorials

On the next screen you should see the words you typed and Use: and the words to use.

If you do not see that, then, look through the terms to see if another term will work.  If you do not see a term to use, there may not be heading in this database for your term.  In that case, just use your words when you do the search.

search terms

Finding Medline Complete terms

On CINAHL's advanced search page (library.purdueglobal.edu/medline), you will see MeSH 2015 located just above the search boxes.  MeSH stands for Medical Subject Headings. Click on MeSH 2015

In the search box on the next screen, type your term. For this example, hand washing was used.

Click on Browse

There is also a link to View Tutorials if you would like additional training.

On the next screen you should see the words you typed and Use: and the words to use.