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EBP & Clinical Inquiry

Online "Textbook" for Clinical Inquiry Internship for Nursing & Allied Health

SEARCHING for evidence

1. Start with your question:  We encourage the PPCO format [See the box below].

2. Break your question into CONCEPTS

3. Identify Synonyms / Alternate Terms for your CONCEPTS

4. Find SUBJECT HEADINGS in the database for your CONCEPTS [Called MeSH in PubMed]. See the Sample Search document  below for how to find the Subject Headings in CINAHL and in PubMed.

  • Search ONE CONCEPT AT A TIME - then combine

5. FOCUS / LIMIT after your initial search-- do not automatically limit to last 5 years, or by study type (Systematic Reviews). You want to see the "body of evidence."

6. Search in at least 2 databases or sources - Preferably CINAHL and PubMed, plus a guideline source (Google doesn't count).

7. Document your search and results (databases searched, keywords/subject headings used, limits applied, # of results)

See step by step process on the Sample Search file below.  It's a simple search - yours may be more complex. Ask for help when you run into challenges. EXPECT it to be challenging.

STRUGGLING with your search?  Contact Frances for help.  

Check in with your EBP Mentor and Manager - let them know where you are in the process, and give them an overview of what you have found - was there a LOT?  Very little?

Refer to EBP Project Portfolio Step 2 which you previously downloaded.

Google and GoogleScholar are NOT good resources for EBP searches. 

  • Information may not be peer reviewed (Google Scholar contains a lot of DNP capstone papers - NOT peer reviewed)
  • Cannot replicate your search - this is why you document your search so someone can repeat it with the same results
  • Use to find synonyms / terminology to use in databases such as PubMed and CINAHL

Search these from anywhere:

 

Carle Library - you will need to be on the Carle Network. CINAHL, PubMed, Cochrane are your "best bets."

PPCO Question format

The purpose of any question format is to determine the CONCEPTS you will use to SEARCH for evidence.

Nursing has long used the PICO question for EBP, borrowed from Medicine, which is often focused on comparing specific diagnoses or treatments. 

PICO can “force” selection of an intervention before a person may have solid background knowledge on a topic. It can lead to selecting an intervention, then searching only for evidence that promotes that intervention, rather than looking at overall evidence to get to the outcome you’re seeking.

We suggest PPCO:

P: Problem

P: Population

C: Change – what has been recommended regarding this problem?

Outcome: - how are outcomes reported? Measured?

Another way to word your question:

What’s the best current evidence regarding:__________________________________

This keeps in mind that “current” is a relative term – for your topic, the current best evidence may have been published in the last 2-3 years. For some topics, the “latest” or best evidence was published 10 years ago (or longer). Frances discourages automatic use of the "last 5 years" limiter.

For example:

If you’re looking to reduce length of stay in hip fracture patients, your main concepts are:

Length of stay and hip fracture 

Reduce is NOT a concept at this point – you’ll want to get an understanding of the issue – AND if you focus just on studies that reduced LOS, you might miss some on the factors that seem to increase LOS – and you ought to be aware of those, as well as interventions that didn’t work.

 

Reviewing Search Results - which articles do I appralse?

When to stop searching? If you start seeing "repeats" of citations -- you have probably reached "search saturation" and can stop.

Once you have results, start "screening" them -- you are NOT going to read every article on the list!  You will likely find some abstracts that don't fit your question well - although keywords matched.

Read the citation and abstract carefully --

  • length of article may be an indicator that it's not a study (2 pages is NOT a study)
  • Type of study will usually be noted in the abstract (Systematic review, RCT, Quality Improvement)
  • Systematic Reviews / Guidelines and Literature Reviews are "best bets" to start. These will cover a number of studies and give you an overview of the evidence. HOWEVER - it can take 12-18 months between finishing writing and publication. So - review other citations that are from about a year before that great Systematic Review, to the present.

The guide below, with examples from CINAHL, can help you as you review results.  Typically, you will:

  • Select several articles (this might be 6-15, depending on your search results and how much literature is available)
  • Get full text - either from the database or ask your librarian 
  • Start a quick appraisal of these -- you may find that of 15, the first 3 aren't really that great as you start reading
  • Determine your "keeper" articles - likely 5-8
  • Do in-depth appraisal with your "keeper" articles -- see the Appraising & Synthesizing tab