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Grading of the quality of evidence and strength of recommendations
| Quality of evidence | Rationale | |
|---|---|---|
| A | High | RCT or meta-analyses |
| B | Moderate | Downgraded RCTs or upgraded observational studies |
| C | Low | Well-done observational studies |
| D | Very low | Case series or expert opinion |
| Strength of recommendation | ||
| Grade 1 | Strong | We recommend |
| Grade 2 | Weak | We suggest |
RCT randomized controlled trial
