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NURS 4000 Evidence-Based Practice (EBP): Module 4: Evaluate


Quality of Evidence

The quality of evidence you find in your research varies based on the nature of its source. The pyramid to the right illustrates this hierarchy, starting at the bottom and improving in quality as it moves from bottom to top. Here is a guide to the levels:

Level I: Evidence from a systematic review or meta-analysis of all relevant randomized controlled trials (RCTs), or evidence-based clinical practice guidelines based on systematic reviews of RCTs

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 case-control and cohort studies

Level V: Evidence from systematic reviews of descriptive and qualitative studies

Level VI: Evidence from a single descriptive or qualitative study

Level VII: Evidence from the opinion of authorities and/or reports of expert committees

Melnyk, BM, & Fineout-Overholt, E: (2011). Evidence-based practice in nursing & healthcare. Philadelphia, PA: Lippincott Williams & Wilkins.

Levels of Evidence

Reading a Scholarly Article