Table 1 EAU Guideline’ levels of evidence and grades of recommendation

1a

Evidence obtained from meta-analysis of randomized trials

1b

Evidence obtained from at least one randomized trial

2a

Evidence obtained from one well-designed controlled study without randomization

2b

Evidence obtained from at least one other type of well-designed quasi-experimental study

3

Evidence obtained from well-designed non-experimental studies, such as comparative studies, correlation studies and case reports

4

Evidence obtained from expert committee reports or opinions or clinical experience of respected authorities

Strong recommendations (for/against)

Advantages of interventions clearly outweigh the disadvantages or the disadvantages clearly outweigh the advantages

Weak recommendations (for/against)

Advantages and disadvantages of interventions are uncertain or the evidence regardless of its quality shows that the advantages and disadvantages are equal