Table 2 Showing statement of evidence and grade of recommendations

A

Requires at least 1 prospective RCT as part of a body of literature of overall good quality and consistency addressing the specific recommendation (evidence levels Ia and Ib)

B

Requires the availability of well conducted clinical studies, but no prospective, randomized clinical trials on the topic of recommendation (evidence levels IIa, IIb, III)

C

Requires evidence obtained from expert committee reports or opinions and/or clinical experiences of respected authorities.

Indicates an absence of directly applicable clinical studies of good quality (evidence level IV)