Table 1.

Grading of Recommendations Assessment, Development and Evaluation quality level of evidence and meaning

Quality level	Definition
High	We are confident that the estimate of the effect is close to the actual effect
Moderate	The estimates of the effect appear to be close to the actual effect but may vary considerably
Low	The confidence in the estimate of the effect is limited. The actual effect may differ significantly from the estimate of the effect
Very low	There is little confidence in the estimate of the effect. The actual effect will differ significantly from the estimate of the effect