Table 1.
Change in patient characteristics according to access sheath usage status.
| Characteristic | Before propensity score matching |
After propensity score matching |
||||
|---|---|---|---|---|---|---|
| UAS+ | UAS− | p-Value | UAS+ | UAS− | p-Value | |
| Patient, n | 481 | 87 | 87 | 87 | ||
| Age, mean±SD, year | 48.5±14.3 | 47.6±13.9 | 0.66 | 51.3±13.6 | 47.6±13.9 | 0.16 |
| Gender (male), n (%) | 279 (58.0) | 52 (59.8) | 0.85 | 57 (65.5) | 52 (59.8) | 0.39 |
| BMI, mean±SD, kg/m2 | 27.3±4.3 | 27.1±2.6 | 0.75 | 26.4±3.0 | 27.1±2.6 | 0.18 |
| Side (right), n (%) | 241 (50.1) | 36 (41.4) | 0.13 | 39 (44.8) | 36 (41.4) | 0.65 |
| Stone burden, median (IQR), mm3 | 577 (237–1133) | 189 (119–781) | 0.004 | 221 (132–918) | 189 (119–781) | 0.22 |
| Stone density, mean±SD, HU | 1004±321 | 1095±398 | 0.24 | 1018±330 | 1095±398 | 0.37 |
| Localization, n (%) | 0.01 | 0.41 | ||||
| Lower calyx | 106 (22.0) | 26 (29.9) | 20 (23.0) | 26 (29.9) | ||
| Multiple localization | 63 (13.1) | 19 (21.8) | 17 (19.5) | 19 (21.8) | ||
| Others | 312 (64.9) | 42 (48.3) | 50 (57.5) | 42 (48.3) | ||
| Multiple stones, n (%) | 195 (40.5) | 47 (54.0) | 0.01 | 41 (47.1) | 47 (54.0) | 0.57 |
| Preoperative double-J stent, n (%) | 152 (31.6) | 15 (17.2) | 0.007 | 27 (31.0) | 15 (17.2) | 0.05 |
| Failed SWL for the same stone, n (%) | 152 (31.6) | 35 (40.2) | 0.15 | 25 (28.7) | 35 (40.2) | 0.15 |
| Perioperative basket usage, n (%) | 362 (75.3) | 30 (34.5) | <0.001 | 42 (48.3) | 30 (34.5) | 0.064 |
BMI, body mass index; IQR, interquartile range; SWL, shock wave lithotripsy; UAS+, patients had ureteral access sheath during procedure; UAS−, patients had no ureteral access sheath during procedure; SD, standard deviation; HU, Hounsfield unit.