BMI, Body mass index, ESWL, Extracorporeal shock wave lithotripsy, ASA, The American Society of Anesthesiologists (ASA) Physical Status Classification

**Each superscript letter denotes a subset of PNL and RIRS categories whose column proportions do not differ significantly from each other at the ,05 level.

^#Mann-Whitney U test

≈Pearson chi-square test

^&Yate’s chi-square test

^¥Exact test

Table 2. Comparison of intra-operative and postoperative outcomes in the PCNL and RIRS groups.