Table 2 Grading of Recommendations, Assessment, Development and Evaluation (GRADE). RCTs randomized controlled trials
Grade of recommendation | Quality of supporting evidence | Implications |
|---|---|---|
1A Strong recommendation, high-quality evidence | RCTs without important limitations or overwhelming evidence from observational studies | Strong recommendation, applies to most patients in most circumstances without reservation |
1B Strong recommendation, moderate-quality evidence | RCTs with important limitations (inconsistent results, methodological flaws, indirect analyses or imprecise conclusions) or exceptionally strong evidence from observational studies | Strong recommendation, applies to most patients in most circumstances without reservation |
1C Strong recommendation low-quality or very low-quality evidence | Observational studies or case series | Strong recommendation but subject to change when higher quality evidence becomes available |
2A Weak recommendation high-quality evidence | RCTs without important limitations or overwhelming evidence from observational studies | Weak recommendation, the best action may differ depending on the patient, treatment circumstances, or social values |
2B Weak recommendation moderate-quality evidence | RCTs with important limitations (inconsistent results, methodological flaws, indirect or imprecise) or exceptionally strong evidence from observational studies | Weak recommendation, the best action may differ depending on the patient, treatment circumstances, or social values |
2C Weak recommendation low-quality or very low-quality evidence | Observational studies or case series | Very weak recommendation; alternative treatments may be equally reasonable and merit consideration |