| Grade A |
Well-conducted RCT or exceptionally strong observational study |
| Grade B |
RCT with some weakness of procedure or generalizability or generally strong observational studies |
| Grade C |
Observational studies that are inconsistent, have small sample sizes, or have other problems that potentially confound interpretation of data |
| Clinical principle |
Statement about a component of clinical care that is widely agreed upon by urologists or other clinicians for which there may or may not be evidence in the medical literature |
| Expert opinion |
Statement, achieved by consensus of a panel, based on members’ clinical training, experience, knowledge |
