Evidence Pyramid
The Evidence Pyramid is a visual representation of the types of publications that make up the nursing/medical literature. Use the pyramid as a guide to help you focus on the best available evidence for supporting your PICOT question.
Level I: Systematic Reviews or Meta-analyses of all relevant Randomized Controlled Trials or clinical practice guidelines based on systematic reviews of RCTs or three or more RCTs of good quality that have similar results.
Level II: Evidence obtained from at least one well-designed RCT
Level III: Evidence obtained from well-designed controlled trials without randomization
Level IV: Evidence from well-designed cohort or case-controlled studies
Level V: Evidence from case series and case reports on the treatment of individual patients
Level VI: Evidence obtained from experts that lack strong methodological quality
Not all evidence is created equal. When searching the literature keep in mind that the strongest evidence (Systematic Reviews and Meta-analyses) is indexed with less frequency than studies with weaker evidence. It can take several or more years to conduct a rigorous systematic review or meta-analysis before being published in a peer-reviewed journal.
Quatitative and Qualitative: What's the difference?
The difference between quantitative and qualitative study designs is in the type of data they collect. Quantitative data is usually numerical, while qualitative data is more descriptive. Both types of study have value, and they often work well together to provide a broader view of your subject.
- See Also: Study Design: Hierarchy of Evidence-Duke University Medical Center Learn to visualize the different levels of evidence hierarchies when searching the literature.
Wondering how to conduct a systematic review? This explainer video from The Evidence Synthesis Academy at Brown University walks you through the basic steps.
American Journal of Nursing Collection: Systematic Reviews Step by Step
Types of EBP Research
Glossary of Terms
- Glossary of terminology-Study DesignsUse this glossary to distinguish between study designs including the advantages and disadvantages of each.
Disclaimer
Non-Mount Carmel organizations referenced on this website are identified for informational purposes only. Mount Carmel is not endorsing these organizations. The services these organizations provide, and the values or opinions they express, may not be consistent with the teachings of the Catholic Church and the Ethical and Religious Directives for Catholic Health Care Services. Mount Carmel makes no representations concerning the conduct or beliefs of these organizations.