Table 5.

Four-levels color schema in order to integrate the quality of evidence assessment and the strength of recommendations.

Level of evidence	High	Moderate	Low	Very low
Grade of recommendation	Consistent evidence from well performed and high quality studies or systematic reviews	Evidence from studies or systematic reviews with few important limitations	Evidence from studies or systematic reviews with some important limitations	Evidence from studies with serious flaws
Class I–Strong recommendation to do Benefits >>> risk	Strong recommendation based on high level of evidence	Strong recommendation based on moderate level of evidence	Strong recommendation based on low level of evidence	Strong recommendation based on expert opinion
Class IIa–Moderate recommendation to do Benefits >> risk	Moderate recommendation based on high level of evidence	Moderate recommendation based on moderate level of evidence	Moderate recommendation based on low level of evidence	Moderate recommendation based on very low level of evidence; diverging expert opinions
Class IIb–Weak recommendation to do Benefits ≥ risks	Weak recommendation based on high level of evidence	Weak recommendation based on moderate level of evidence	Weak recommendation based on low level of evidence	Weak recommendation based on very low level of evidence; diverging expert opinion
Class III–Recommendation not to do No benefit/Potentially harm	Recommendation based on high level of evidence	Recommendation based on moderate level of evidence	Recommendation based on low level of evidence	Recommendation based on very low level of evidence

Colors represent the strength of recommendation regarding the investigated intervention (i.e., use of AD) based on the level of evidence. Green, yellow and orange represent strong, moderate and weak recommendation to use AD, respectively, while red means recommendation not to use AD.