JHNEBP EVIDENCE RATING SCALES

© The Johns Hopkins Hospital/The Johns Hopkins University

SSTTRREENNGGTTHH of the Evidence
Level I Experimental study/randomized controlled trial (RCT) or meta analysis of RCT
Level II Quasi-experimental study
Level III Non-experimental study, qualitative study, or meta-synthesis.
Level IV Opinion of nationally recognized experts based on research evidence or expert

consensus panel (systematic review, clinical practice guidelines)
Level V Opinion of individual expert based on non-research evidence. (Includes case

studies; literature review; organizational experience e.g., quality improvement
and financial data; clinical expertise, or personal experience)

QQUUAALLIITTYY of the Evidence

A High

Research consistent results with sufficient sample size, adequate control, and definitive conclusions; consistent
recommendations based on extensive literature review that includes thoughtful reference to scientific
evidence.

Summative
reviews

well-defined, reproducible search strategies; consistent results with sufficient numbers of well defined
studies; criteria-based evaluation of overall scientific strength and quality of included studies; definitive
conclusions.

Organizational well-defined methods using a rigorous approach; consistent results with sufficient sample size; use of
reliable and valid measures

Expert Opinion expertise is clearly evident
B Good Research reasonably consistent results, sufficient sample size, some control, with fairly definitive conclusions;

reasonably consistent recommendations based on fairly comprehensive literature review that includes some
reference to scientific evidence

Summative
reviews

reasonably thorough and appropriate search; reasonably consistent results with sufficient numbers of well
defined studies; evaluation of strengths and limitations of included studies; fairly definitive conclusions.

Organizational Well-defined methods; reasonably consistent results with sufficient numbers; use of reliable and valid
measures; reasonably consistent recommendations

Expert Opinion expertise appears to be credible.
C Low quality

or major
flaws

Research little evidence with inconsistent results, insufficient sample size, conclusions cannot be drawn
Summative
reviews

undefined, poorly defined, or limited search strategies; insufficient evidence with inconsistent results;
conclusions cannot be drawn

Organizational Undefined, or poorly defined methods; insufficient sample size; inconsistent results; undefined, poorly
defined or measures that lack adequate reliability or validity

Expert Opinion expertise is not discernable or is dubious.
*A study rated an A would be of high quality, whereas, a study rated a C would have major flaws that raise serious questions about the
believability of the findings and should be automatically eliminated from consideration.

Newhouse R, Dearholt S, Poe S, Pugh LC, White K. The Johns Hopkins Nursing Evidence-based Practice Rating Scale. 2005. Baltimore, MD,

The Johns Hopkins Hospital; Johns Hopkins University School of Nursing.