EBM Resources

I.  Articles from American Family Physician


2. Strength of Recommendation Taxonomy (SORT): A Patient-Centered Approach to Grading Evidence in the Medical Literature
Article from the February 1, 2004, issue of American Family Physician that describes the SORT evidence rating system, which allows authors to rate individual studies or bodies of evidence.  To see examples of SORT tables, please look at any review article in AFP.

3.  How to Write an Evidence-Based Clinical Review Article
Article from the January 15, 2002, issue of American Family Physician that presents guidelines for writing an evidence-based clinical review article. NOTE: American Family Physician no longer includes ratings of evidence in the text for individual studies as described in "How to Write an Evidence-Based Clinical Review Article."  Instead, we use the SORT evidence rating system to rate bodies of evidence for key clinical recommendations on diagnosis and treatment.

4. Editorial: Evidence-based Medicine—Common Misconceptions, Barriers, and Practical Solutions
Editorial in the upcoming September 15, 2018 issue of American Family Physician.

II.  Other Resources


Centre for Evidence-Based Medicine(
Promotes evidence-based health care, and provides support and resources for the teaching and practice of evidence-based medicine.

Evidence-based Medicine Toolbox(
Contains tools and resources for the teaching and practice of evidence-based medicine.

Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group(
Provides information about grading quality of evidence and strength of recommendations.

Provides a collection of EBM resources including textbooks, podcasts, education guides, and glossaries.


Free Access


McMaster University’s compendium of pre-appraised evidence to support clinical decisions.  Content is presented in a hierarchical way, with the highest level of available evidence listed first.

Agency for Healthcare Research and Quality(
In particular, see AHRQ’s Effective Healthcare Reports( on various clinical topics.
Note: many of  these reports are published in AFP under the “Implementing AHRQ Effective Health Care Reviews” department collection.

Cochrane Database of Systematic Reviews(
Free for abstracts only, which in most cases provide the key findings of interest. The complete review requires a subscription. The Cochrane database contains systematic reviews of narrowly focused clinical questions (e.g., “Colchicine for treating acute gout attacks”) as opposed to broad, general reviews of topics (e.g., “Management of an acute gout attack”).
Note: AFP publishes summaries of Cochrane abstracts in “Cochrane for Clinicians.”

ECRI Guidelines Trust(

Repository of evidence-based clinical practice guidelines, appraised using the National Academy of Medicine’s Standards for Trustworthy Clinical Practice Guidelines. 

National Center for Complementary and Integrative Health( 
Although NCCIH has been criticized for political interference and questionable science, we include it in this list because there are few freely available comprehensive sources of information in this field.

Trip( (Turning Research Into Practice)
Contains links to a wide range of journal articles, medical organization clinical guidelines, online medical references, and other sources.  A limited version is freely available; additional content requires an annual subscription.

U.S. Preventive Services Task Force(
Premier source of evidence-based, graded recommendations for clinical preventive services.
Note: AFP publishes Recommendations and Reports from the USPSTF as well as CME case studies in the Putting Prevention Into Practice series.

Subscription Required
Most of these are point-of-care clinical information and decision support tools. These sites provide important background information, but authors should review the primary source to use as a citation for the article.


Essential Evidence Plus(
Includes POEMS (collections of patient-oriented evidence that matters).

Natural Medicines Comprehensive Database(
Reviews of the use of natural medicines in the treatment of various diseases.

Natural Medicines(
Database of dietary supplements, natural medicines, and complementary, alternative, and integrative therapies.



To ensure adequate searching on your topic, we strongly recommend that  the above sources be reviewed, in addition to a PubMed search using the Clinical Query function ( This is done by using the provided link, or by going to the PubMed home page, and selecting “Clinical queries” from the lower center of the screen.

Sample Data Sources paragraph:

Data Sources: A PubMed search was completed in Clinical Queries using the key terms gout and hyperuricemia.  The search included meta-analyses, randomized controlled trials, clinical trials, and reviews. Also searched were the Agency for Healthcare Research and Quality Effective Healthcare Reports, the Cochrane database, DynaMed, and Essential Evidence Plus. November 18, 2017.


AFP has partnered with MDCalc as the resource for clinical calculators, such as the Centor Score (Modified/McIsaac) for Strep Pharyngitis, the CHA₂DS₂-VASc Score for Atrial Fibrillation Stroke Risk, the Revised Cardiac Risk Index for Pre-Operative Risk, and the Wells' Criteria for Pulmonary Embolism. MDCalc is available online( and via smartphone app at MDCalc Medical Calculator.

The following online calculators perform statistical calculations, such as number needed to treat, odds/probability converter, positive and negative likelihood ratios, positive and negative predictive values, and posttest probability.

ClinCalc (free)
Relative risk or risk ratio from an odds ratio(
Number needed to treat(

EBM Toolbox( (free)
Diagnostic test calculator( (sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values, post-test probability)
Randomized controlled trial calculator(
Prospectdive study calculator(
Case-control study calculator(
Odds Ratio to NNT Converter(

MedCalc( (free)
Sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values, post-test probability.