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“I like my coffee (and my evidence) strong!”

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Let’s say you are still working to solve the issue of whether gum chewing reduces post-operative ileus. You identified titles of all relevant articles using PubMed database (http://www.ncbi.nlm.nih.gov/pubmed), and had the librarian pull the full articles for you.

Now you find yourself looking at a formidable stack of articles on the topic. You are sure that some are probably better quality than coffee2others, but how can you tell?

Professionals have agreed on which types of evidence are strongest. Here’s one well-accepted hierarchy form strongest #1 to weakest #6 (Melnyk & Fineout-Overholt, 2005).

  1. Systematic reviews, Meta-analyses, or Evidence-based clinical practice guidelines based on systematic review of RCTs
  2. Randomized controlled trial
  3. Controlled trials without randomization
  4. Case controlled or cohort studies
  5. Systematic review of descriptive studies
  6. Single descriptive or qualitative study
  7. Expert opinion of individuals or committees

Number 1= Strongest.   Number 6=Weakest

When you are trying to solve a problem, FIRST look for the three (3) types of evidence that are the very strongest (#1). These are:

  1. Systematic reviews that are summaries of research findings from many studies;
  2. Meta-analyses that are summaries of research findings in which the data from those other studies are combined into one big study;
  3. Evidence-based clinical practice guidelines that are clinical recommendations based on a summary of research and other evidence. An expert panel has often agreed on the summary and recommendations.

Your next strongest option, #2, is at least one randomized controlled trial (RCT). In an RCT a group of subjects is randomly separated into at least two groups. One group gets the experimental treatment—whether it is a drug or teaching plan or something else—and the other group usually gets standard treatment or a placebo. Then the group outcomes are compared statistically to see which did better.

Usually the title or first few lines of the article will tell you that the article is a systematic review, a meta-analysis, an evidence-based clinical practice guideline, or an RCT. Rarely is this left a mystery! (Never assume that a research study article is strong just because you LIKE the findings, or that it is weak because you DON’T like the findings.)

I’ll comment on other levels of evidence soon, but let’s focus on the strongest types first. Try the critical thinking for practicing the ideas above.

Critical Thinking:  Using the article titles below, rank these three (3) research studies in order from Strongest evidence to Weakest evidence:

Want to read more?  A good summary of one hierarchy is and why it’s important is at this 5 minute youtube video: https://www.youtube.com/watch?v=5H8w68sr0u8 . While that hierarchy does not precisely match the one above, the video still has lots of good information.

 

 

Evidence based nursing, Literature review

How to Re-Invent the Wheel (NOT!!)

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You can avoid re-inventing the wheel by checking in with top notch wheelexperts who have already examined the practice problem that you face.

In other words, it’s time to head to the library. After all that’s what the library is: the experiences and research written down by experts, who have spent a lot of time thinking about the same problem that you are facing. Really it’s pretty amazing that we have access to health professionals all over the world who are eager to help you avoid re-inventing the wheel.imagesCAGYW6WB

The best experts in the field are talking directly to you through their publications!

Of course it’s important to ask your colleagues in your own and other institutions about their ideas on the problem, but that’s not enough. You will be limited by what they happen to know; or worse you will be limited by what they don’t happen to know! Nurses on your floor can provide practical, site-specific insights, but it’s easy to see why you would want to add newest information from the top experts. That is BEST evidence.

Remember: EBP = Best evidence + Clinical judgment + Patient/family preferences/values

HOW do you find the experts in the library?

  1. The first step is to identify KEY WORDS from your PICO.
  2. Use single words or put phrases in parenthesis in your list of words (e.g., “postoperative ileus”). A librarian can help with key words, too.
  3. Google the site PubMed (PubMed is a complete database of healthcare publications)
  4. In the search box at the top of the PubMed page, type in your key words
  5. You will get a list of articles on your topic (and some related articles on the right side)
  6. Click on the box beside the ones that you want & email that list tocomputers shaking hands your facility librarian with a request to pull the complete articles for you! (Of course if you are a student with some direct access to full-text articles in a school library, then it may be quicker to get them on your own. It’s up to you, but part of your “village that it takes” might be the librarian.) [See “Take five!” if you want more on to why PubMed beats Google Scholar.]

EXAMPLE: Let’s get specific….

  • Take this problem that we have discussed before:
    • P = Postoperative patients with ileus (Population or Problem)
    • I = Gum chewing postop (Intervention to try out)
    • C = NPO with gradual diet progression when bowel sounds start returning (Comparison intervention)
    • O = Reduce time of postop ileus with sooner return to nutritious eating (Outcome that you want)
  • What are some key words from the above PICO stated problem? “Postoperative ileus” adults “gum chewing”
  • Go ahead. Pull up PubMed. Paste in the key words You should get 11 articles about gum chewing & postoperative ileus. Check the boxes of the ones you want, then…
  • Click on the “SEND TO” link near the upper right corner of the screen and email the list to the librarian with a request for full-text of the articles. (You can send to yourself, too)
  • Congratulate yourself on an EBP literature search well-started!

CRITICAL THINKING: Why wouldn’t you simply use google.com to find expert opinions?  [If you want more “data”  related to this question.  Check out“Take five!”]

FOR MORE INFO: Check out this tutorial on how PubMed works & what’s in it http://www.nlm.nih.gov/bsd/disted/pubmedtutorial/020_010.html You pay for PubMed through your taxes—get your $$ worth!