Evidence Based Practice Diagram

Levels of Evidence

EBP graphic illustration

Hierarchy of Evidence

Level I - Evidence from a systematic review or meta-analysis of all relevant randomized controlled trials (RCTs) or three+ RCTs of good quality with similar results.

Level II - Evidence from at least one well-designed RCTs

Level III - Evidence obtained from well-designed controlled trials without randomization (i.e. quasi-experimental).

Level IV - Evidence from well-designed case-control or cohort studies

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

Level VI - Evidence from single descriptive or qualitative studies

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

Ackley, B. J., Swan, B. A., Ladwig, G., & Tucker, S. (2008). Evidence-based Nursing Care Guidelines: Medical-surgical Interventions. (p. 7)St. Louis, MO: Mosby Elsevier.

Evidence Based Practice

Measurement Tools

Types of Resources

Hierarchy of Evidence Resources - Nursing - Research Guides at University  of Michigan Library

Haynes RB. Of studies, syntheses, synopses, summaries and systems: the “5S" evolution of services for evidence-based health care decisions. ACP J Club. 2006 Nov-Dec;145(3):A8-9. 


P = Patient or Problem - Patients age 65 and older with high blood pressure

I = Intervention - Patient education

C = Comparison - No patient education

O = Outcome - Patient participation in exercise


NIH. National Library of Medicine.




Problem, Patient, Action, Alternative, Patient Results, Evidence


Patient Reported Outcome Measures

Qualitative versus Quantitative

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