Nursing

When dealing with EBP, you will often hear about the “best” evidence. This means two things:

1. Not all evidence is created equal.
2. Not all levels of evidence are available for every question.

Imagine you had a patient with recurring, painful acne. What kind of research would you seek to help deliver a treatment:

• a systematic review of several randomized controlled trials of treatments for this condition,
• a single case study of a patient experiencing similar symptoms,
• or a professor who once mentioned they believe “chocolate causes acne”? 

These are all forms of evidence—even the last one!—but something like a systematic review, which amasses data from numerous studies to create generalizable results, will provide the broadest view of the evidence on your patient’s condition and help you devise an evidence-based treatment plan.

(Image from CFCF / CC BY-SA)

However, sometimes the very high levels of evidence aren’t available. As you seek higher levels of evidence, they become less common, as shown in the pyramid above. With an especially narrow topic, or one about a new phenomenon, a single case study may be the best you can find. Additionally, for some types of questions—etiology or harm, for instance—it may not be ethically possible for a randomized controlled trial to exist.

Resources:

Critical Appraisal is the process of ensuring the research you've discovered meets a baseline of reliability. According to LoBiondo-Wood & Haber (2017):

The critical appraisal of research studies is an organized, systematic approach to evaluating a research study...using a set of standardized critical appraisal criteria. The criteria are used to objectively determine the strength, quality, quantity, and consistency of evidence provided by the available literature to determine its applicability to practice, policy, and education.

Functionally, this means not taking every article you find at face value. Sadly, there are bad actors in the world of scholarly publishing who promote poor research for personal gain, and your responsibility as a practitioner of EBP is to be well-informed and scrupulous: a true master of information literacy.

Fortunately, there are numerous resources and guides to appraise an article. This is a major endeavor, and as you might imagine, different study types and questions require different forms of appraisal. The links below should get you started, but if you ever have a question about the validity of a source, don't hesitate to contact your librarian!

Resources:

How to Read a Paper Series, by Trisha Greenhalgh: