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Evidence Based Practice Guide for Nursing Students: Appraisal

Introductory Guide for BSN, RN to BSN, BRAND, Nursing MS and DNP students at University of Wyoming.

What is Critical Appraisal?

Critical Appraisal

Critical appraisal is an essential part of the Evidence Based Practice process. Critical appraisal identifies possible flaws or problems with the study methodology, the transparency of the study design as written in the article, the quality of the research, and  level of evidence.

Appraisal Concepts - Validity & Reliability

What is validity?

Internal validity is the extent to which the experiment demonstrated a cause-effect relationship between the independent and dependent variables.

External validity is the extent to which one may safely generalize from the sample studied to the defined target population and to other populations.

What is reliability?

Reliability is the extent to which the results of the experiment are replicable.  The research methodology should be described in detail so that the experiment could be repeated with similar results.

More Useful Scientific Terminology

Critically Appraised Topics (CATS)

CATs are critical summaries of a research article.  They are concise, standardized, and provide an appraisal of the research.

If a CAT already exists for an article, it can be read quickly and the clinical bottom line can be put to use as the clinician sees fit.  If a CAT does not exist, the CAT format provides a template to appraise the article of interest.

Evaluating a Study

Start by asking simple questions about the article:

  • Have the study aims been clearly stated?
  • Does the sample accurately reflect the population?
  • Has the sampling method and size been described and justified?
  • Have exclusions been stated?
  • Is the control group easily identified?
  • Is the loss to follow-up detailed?
  • Are enough details included so that the results could be replicated?
  • Are there confounding factors?
  • Are the conclusions logical?
  • Do the findings match the study aims?
  • Can the results be extrapolated to other populations?

Attribution Statement: University of Illinois Chicago. Library of the Health Sciences. Evidence Based Medicine. https://researchguides.uic.edu/ebm. Used under a CC BY-NC license.