3.7. Risk of Bias Assessment
The MINORS scores of the five prospective cases in the KTP group averaged 13.1 (SD, 1.45; range, 11-15) (Appendix S3), suggesting the fair quality of evidence. The scores of the 10 prospective studies in the CO2 group averaged 13.6 (SD, 1.52; range, 12-15), suggesting the fair quality of evidence. No statistical difference existed between the MINOR scores of the abovementioned two groups (p>0.05).