SORT: Rating the Strength of Evidence

American Family Physician and other family medicine journals use the Strength of Recommendation Taxonomy (SORT) system for rating bodies of evidence for key clinical recommendations. (For additional background, please see Strength of Recommendation Taxonomy (SORT): A Patient-Centered Approach to Grading Evidence in the Medical Literature, an explanatory article published in the February 1, 2004, issue of AFP), as well as this guidance for rating the strength of evidence(110 KB PDF).
The SORT table is intended to highlight the most important three to seven recommendations for clinicians from a review article. Each recommendation is accompanied by a SORT rating of A, B, or C as defined below to emphasize interventions and approaches that improve patient-oriented outcomes (e.g. morbidity, mortality, quality of life) over disease-oriented evidence (e.g. biomarkers, surrogate endpoints). More details about creating a SORT table can be found in the Authors Guide.

STRENGTH OF RECOMMENDATION: ADEFINITION: Recommendation based on consistent and good quality patient-oriented evidence.*
STRENGTH OF RECOMMENDATION: BDEFINITION: Recommendation based on inconsistent or limited quality patient-oriented evidence.*
STRENGTH OF RECOMMENDATION: CDEFINITION: Recommendation based on consensus, usual practice, expert opinion, disease-oriented evidence,** and case series for studies of diagnosis, treatment, prevention, or screening
STRENGTH OF RECOMMENDATION: * Patient-oriented evidence measures outcomes that matter to patients: morbidity, mortality, symptom improvement, cost reduction, quality of life.
** Disease-oriented evidence measures intermediate, physiologic, or surrogate endpoints that may or may not reflect improvements in patient outcomes (e.g., blood pressure, blood chemistry, physiological function, and pathological findings).