Table 3

Quality of evidences according to the Scottish Intercollegiate Guidelines Network

AAt least one meta-analysis, systematic review or randomised clinical trial classified as 1++ and directly applicable to the target population
Studies classified as 1+ and directly applicable to the target population
BStudies classified as 2++ and directly applicable to the target population
Evidences from studies classified as 1++ or 1+, but not directly applicable to the target population
CStudies classified as 2+ and directly applicable to the target population
Evidences from studies classified as 2++, but not directly applicable to the target population
DEvidence level 3 or 4
Evidences from studies classified as 2+, but not directly applicable to the target population