The Clinical Question

Study Designs

Evidence Sources

Critical Appraisal

Applying Evidence

Saving Time

EBVM Resources


Critical Appraisal of the Literature

Topics Covered

Initial Screen
Critical Appraisal

Critical appraisal is an essential component of EBM. Clinicians must have the skills to evaluate a research study and the expertise to determine the applicability of the study's results to a specific patient. During the search process, you should search for the appropriate study design for your clinical question. [See: Types of Clinical Questions and Study Designs]. If you cannot find the best study design for your question, you should move a step down to the next best study design, and so on, until you find the best available evidence.

Initial Screen
Once you have found an article that seems to address your question, Rosenthal suggests giving it an "initial validity and relevance screen." This will help you determine whether to spend the time reading and evaluating the study in depth. He offers the following eight questions to help veterinarians decide whether the article is worth an in depth review.

1. Is the article from a peer reviewed journal?
2. Is the location of the study similar to mine so that results, if valid, would apply to my practice?
3. Is the study sponsored by an organization that might influence the study design or results?
4. If the results are true, will there be a direct impact on the health of my patients?
5. If there is an impact on the health of my patients, will the owner of the animal care?
6. Is the problem addressed one that is common in my practice?
7. Is the test or intervention feasible and available to me?
8. If it is true, will the information require me to change my practice?

Critical Appraisal
JAMA published a series of User's Guides designed to teach clinicians how to read and appraise research articles. These guides encourage clinicians to ask the following three questions as a framework for evaluation:

1. Are the results of the study valid?
2. How strong and/or useful are the recommendations?
3. Will the results help me in managing my patients?

Assembled here are some of the JAMA User Guides which will be most useful to veterinarians. Accompanying a link to each user guide is a corresponding Appraisal Guide and a link to the PubMed citation for a sample article. The Appraisal Guides are part of an Evidence Based Tool Kit are adapted from the Users' Guides series. The Appraisal Guides will help to walk you through the critical appraisal. If you do not have access to the sample article, feel free to appraise a substitute article. The idea is to get you practicing those critical appraisal skills!

Statistics Glossary: This glossary from the STEPS (STatistical Education through Problem Solving) consortium may prove to be a good reference tool as you refamiliarize yourself with statistical concepts and terms.

Systematic Review:

Therapy or Prevention:




Economic Analysis


Next: Applying Evidence