Table 4.

An overview of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.⁴⁷

GRADE: Strength of evidence
High quality:
Further research is very unlikely to change our confidence in the estimate of effect
Moderate quality:
Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Low quality:
Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Very low quality:
Any estimate of effect is very uncertain
GRADE: Strength of recommendation
Recommendations can be categorized as either Strong or Weak. Recommendations involve a trade-off between benefits and harms. Those making a recommendation should consider four main factors:
• The trade-offs, taking into account the estimated size of the effect for the main outcomes, the confidence limits around those estimates, and the relative value placed on each outcome
• The quality of the evidence
• Translation of the evidence into practice in a specific setting, taking into consideration important factors that could be expected to modify the size of the expected effects, such as proximity to a hospital or availability of necessary expertise
• Uncertainty about baseline risk for the population of interest. If there is uncertainty about translating the evidence into practice in a specific setting, or uncertainty about baseline risk, this may lower our confidence in a recommendation.