This was successfully posted to your pofile.
This box will close automatically in a few seconds. Close this window
We don't have an e-mail address on file for you. To use AAFP Connection, you must have an e-mail address in our records. Click Here
Strength of Recommendation Taxonomy (SORT)
An alternative way to understand the significance of a strength-of-recommendation grade is through the algorithm generally followed by authors and editors in assigning grades based on a body of evidence (Figure 1). While this algorithm provides a general guideline, authors and editors may adjust the strength of recommendation based on the benefits, harms, and costs of the intervention being recommended.
|Strength of recommendation||Basis for recommendation|
|A||Consistent, good-quality patient-oriented evidence*|
|B||Inconsistent or limited-quality patient-oriented evidence*|
|C||Consensus, disease-oriented evidence,* usual practice, expert opinion, or case series for studies of diagnosis, treatment, prevention, or screening|
*-Patient-oriented evidence measures outcomes that matter to patients: morbidity, mortality, symptom improvement, cost reduction, and quality of life. Disease-oriented evidence measures intermediate, physiologic, or surrogate end points that may or may not reflect improvements in patient outcomes (e.g., blood pressure, blood chemistry, physiologic function, pathologic findings).
|Study quality||Diagnosis||Treatment/prevention/ screening||Prognosis|
|Level 1: good-quality, patient-oriented evidence||Validated clinical decision rule
SR/meta-analysis of high-quality studies
High-quality diagnostic cohort study*
|SR/meta-analysis or RCTs with consistent findings
High-quality individual RCT†
|SR/meta-analysis of good-quality
Prospective cohort study
with good follow-up
|Level 2: limited-quality patient-oriented evidence||Unvalidated clinical decision rule
SR/meta-analysis of lower quality studies or studies with inconsistent findings
Lower quality diagnostic cohort study or diagnostic case-control study
|SR/meta-analysis of lower quality clinical trials or of studies with inconsistent findings
Lower quality clinical trial
|SR/meta-analysis of lower quality cohort studies or with inconsistent results
Retrospective cohort study or prospective cohort study with poor follow-up
|Level 3: other evidence||Consensus guidelines, extrapolations from bench research, usual practice, opinion, disease-oriented evidence (intermediate or physiologic outcomes only), or case series for studies of diagnosis, treatment, prevention, or screening|
SR = systematic review; RCT = randomized controlled trial.
|Consistent||Most studies found similar or at least coherent conclusions (coherence means that differences are explainable).|
|If high-quality and up-to-date systematic reviews or meta-analyses exist, they support the recommendation.|
|Inconsistent||Considerable variation among study findings and lack of coherence|
|If high-quality and up-to-date systematic reviews or meta-analyses exist, they do not find consistent evidence in favor of the recommendation.|
- Ebell MH, Siwek J, Weiss BD, Woolf SH, Susman J, Ewigman B, et al. Strength of Recommendation Taxonomy (SORT): a patient-centered approach to grading evidence in the medical literature. Am Fam Physician 2004;69:549-57.