Table 2 Defined grades of evidence and recommendations [AAP ref]
Grade | Research | Preponderance of benefit over harm | Balance of benefit and harm |
|---|---|---|---|
A | Well designed RCTs or diagnostic studies | Strong recommendation | Option |
B | RCT or diagnostic studies with minor limitations; overwhelming consistent evidence from observational studies | Strong recommendation / recommendation | Option |
C | Observation studies (case control and cohort design) | Recommendation | Option |
D | Expert opinion; case reports; reasoning from first principles | Option | No recommendation |