Summary of GRADE recommendations for grading levels of evidence
| Grade . | Description . | Grade . | Description . |
|---|---|---|---|
| 1 | Evidence suggests strongly that the benefit of the procedure outweighs potential risks or risks of the procedure outweigh potential benefits | A | Consistent evidence from systematic reviews or high-quality randomized studies or high-quality observational studies |
| 2 | Evidence suggests the benefit and risk of a procedure are finely balanced or uncertain | B | Evidence from randomized and observational studies with important methodologic flaws |
| C | Evidence from randomized and observational studies with major methodologic flaws or other sources of evidence (eg, case series) |
| Grade . | Description . | Grade . | Description . |
|---|---|---|---|
| 1 | Evidence suggests strongly that the benefit of the procedure outweighs potential risks or risks of the procedure outweigh potential benefits | A | Consistent evidence from systematic reviews or high-quality randomized studies or high-quality observational studies |
| 2 | Evidence suggests the benefit and risk of a procedure are finely balanced or uncertain | B | Evidence from randomized and observational studies with important methodologic flaws |
| C | Evidence from randomized and observational studies with major methodologic flaws or other sources of evidence (eg, case series) |
Reprinted from Crowther et al with permission.4
Each recommendation in the guideline is given a numeric score, which denotes how likely the patient is to gain benefit from the intervention, and a letter, which demonstrates the strength of the evidence.