Table 1. Baseline characteristics of the development group and validation group.
| Development group(n = 747) | Validation group (n = 317) |
Z/χ2 | P Value | |
|---|---|---|---|---|
| Gender (%) | 0.912 | 0.346 | ||
| Male | 422(56.5) | 169(53.3) | ||
| Female | 325(43.5) | 148(46.7) | ||
| Age, year | 53(43~63) | 52(43~64) | 0.298 | 0.765 |
| Diabetes (%) | ||||
| No | 677(90.6) | 281(88.6) | 0.978 | 0.323 |
| Yes | 70(9.4) | 36(11.4) | ||
| Hypertension (%) | ||||
| No | 567(75.9) | 225(71.0) | 2.838 | 0.105 |
| Yes | 180(24.1) | 92(29.0) | ||
| Previous surgery of calculi (%) | 0.591 | 0.472 | ||
| No | 573(76.7) | 250(78.9) | ||
| Yes | 174(23.3) | 67(21.1) | ||
| Functional solitary kidney (%) | ||||
| No | 691(92.5) | 292(92.1) | 0.048 | 0.802 |
| Yes | 56(7.5) | 25(7.9) | ||
| Maximum diameter of calculi, mm | 10(7~14) | 10(6–14) | 0.092 | 0.927 |
| Minimum diameter of calculi, mm | 6(5~8) | 6(4~8) | 1.002 | 0.316 |
| Mean CT attenuation value of calculi, Hu | 0.715 | 0.699 | ||
| <500 | 441(59.0) | 195(61.5) | ||
| 500~1000 | 251(33.6) | 102(32.2) | ||
| >1000 | 55(7.4) | 20(6.3) | ||
| Laterality of calculi (%) | 0.569 | 0.461 | ||
| Left | 377(50.5) | 168(53.0) | ||
| Right | 370(49.5) | 149(47.0) | ||
| Location of calculi (%) | 1.850 | 0.397 | ||
| Upper | 382(51.2) | 162(51.1) | ||
| Middle | 116(15.5) | 40(12.6) | ||
| Lower | 249(33.3) | 115(36.3) | ||
| Ipsilateral renal calculi (%) | 2.490 | 0.119 | ||
| No | 442(59.2) | 171(53.9) | ||
| Yes | 305(40.8) | 146(46.1) | ||
| Mean CT attenuation value of hydronephrosis, Hu | 2.127 | 0.345 | ||
| <8 | 573(76.7) | 231(72.9) | ||
| 8~16 | 132(17.7) | 68(21.4) | ||
| >16 | 42(5.6) | 18(5.7) | ||
| Degree of hydronephrosis (%) | 3.769 | 0.152 | ||
| Mild | 454(60.8) | 173(54.6) | ||
| Moderate | 164(22.0) | 84(26.5) | ||
| Severe | 129(17.2) | 60(18.9) | ||
| Urine WBC count (%) | 0.761 | 0.859 | ||
| No | 384(51.4) | 155(48.9) | ||
| Weakly positive | 184(24.6) | 81(25.6) | ||
| Moderately positive | 100(13.4) | 43(13.6) | ||
| Strongly positive | 79(10.6) | 38(12.0) | ||
| Urine nitrite (%) | 0.191 | 0.669 | ||
| No | 705(94.4) | 297(93.7) | ||
| Yes | 42(5.6) | 20(6.3) |
CT, computer tomography; WBC, white blood cells.