Skip to Main Content

Evidence Based Practice (NUR 4169)

Evidence Pyramid

An evidence pyramid visually depicts the evidential strength of different research designs. The image below is one of several available renderings of an evidence pyramid. Studies with the highest internal validity, characterized by a high degree of quantitative analysis, review, analysis, and stringent scientific methodology, are at the top of the pyramid. Observational research and expert opinion reside at the bottom of the pyramid.


From SUNY: and John Moritz Library's EBP LibGuide.

WATCH THESE: Easy overviews of systematic reviews & meta-analysis

Systematic Reviews Made Simple!
Watch this video for a great overview of Systematic Reviews: What they are, why we need them, and a real-life example of how practical they are.

Meta-Analysis Made More Fun!
Now check out this video for a great explanation of Meta-analysis: What they are/How they work, controversies, and a real-life example of how to critically appraise them.

How to find the highest level of evidence for your clinical question

KEEP IN MIND: Different types of research studies are better suited to answer different categories of clinical questions. This means you might not always find the highest level of evidence (i.e., systematic review or meta-analysis) to answer your question. When this happens, just work your way down the Evidence Pyramid to the next highest level of evidence.

 Which treatment does more harm than good?

RCT → Cohort Study → Case Control → Case Series

Diagnosis: Which diagnostic test should I use? 

Prospective, blind comparison to a gold standard, ie. A controlled trial that looks at patients with varying degrees of an illness and administers both diagnostic tests -- the test under investigation and the "gold standard" test -- to all of the patients in the study group.

Prognosis: What is the patient's likely clinical course over time?

Cohort Study → Case Control → Case Series

Etiology/Harm: What are the causes of this disease or condition?

RCT → Cohort Study→ Case Control → Case Series

Prevention: How do we reduce the chance of disease by identifying and modifying risk factors? 

RCT → Cohort Study → Case Control → Case Series

Cost: Is one intervention more cost-effective than another?

Economic Analysis

Quality of Life: What will be the patient's quality of life following an intervention?

Qualitative Study 

From: John Moritz Library's EBP LibGuide.