Table 1 Characteristics of patients
|  | SEER set (n = 627) | Training set (n = 435) | Internal volidation set (n = 192) | p value | Enternal Volidation set (n = 41) | p value |
|---|---|---|---|---|---|---|
Age (year), n (%) | Â | Â | Â | Â | Â | Â |
 < 80 | 488 (77.83) | 346 (79.54) | 142 (73.96) | 0.121 | 34 (82.93) | 0.444 |
 >  = 80 | 139 (22.17) | 89 (20.46) | 50 (26.04) |  | 7 (17.07) |  |
Race, n (%) | Â | Â | Â | Â | Â | Â |
 Black | 34 (5.42) | 28 (6.44) | 6 (3.12) | 0.190 | 0 (0.00) | 0.001 |
 White | 562 (89.63) | 384 (88.28) | 178 (92.71) |  | 0 (0.00) |  |
 Othera | 31 (4.94) | 23 (5.29) | 8 (4.17) |  | 41 (100.00) |  |
Sex, n (%) | Â | Â | Â | Â | Â | Â |
 Male | 506 (80.70) | 346 (79.54) | 160 (83.33) | 0.267 | 39 (95.12) | 0.021 |
 Female | 121 (19.30) | 89 (20.46) | 32 (16.67) |  | 2 (4.88) |  |
Marital status, n (%) | Â | Â | Â | Â | Â | Â |
 Married | 396 (63.16) | 274 (62.99) | 122 (63.54) | 0.791 | 38 (92.68) | 0.001 |
 Single | 200 (31.90) | 141 (32.41) | 59 (30.73) |  | 3 (7.32) |  |
 Unknown | 31 (4.94) | 20 (4.60) | 11 (5.73) |  | 0 (0.00) |  |
AJCC stage, n (%) | Â | Â | Â | Â | Â | Â |
 Ib | 209 (33.33) | 149 (34.25) | 60 (31.25) | 0.233 | 14 (34.15) | 0.001 |
 II | 168 (26.79) | 107 (24.60) | 61 (31.77) |  | 8 (19.51) |  |
 III | 81 (12.92) | 61 (14.02) | 20 (10.42) |  | 14 (34.15) |  |
 IV | 169 (26.95) | 118 (27.13) | 51 (26.56) |  | 5 (12.19) |  |
AJCC T, n (%) | Â | Â | Â | Â | Â | Â |
 Ta | 18 (2.87) | 13 (2.99) | 5 (2.60) | 0.300 | 1 (2.44) | 0.973 |
 Tis | 6 (0.96) | 5 (1.15) | 1 (0.52) |  | 0 (0.00) |  |
 T1 | 196 (31.26) | 138 (31.72) | 58 (30.21) |  | 15 (36.58) |  |
 T2 | 232 (37.00) | 171 (39.31) | 61 (31.77) |  | 14 (34.15) |  |
 T3 | 94 (14.99) | 60 (13.79) | 34 (17.71) |  | 6 (14.63) |  |
 T4 | 81 (12.92) | 48 (11.03) | 33 (17.19) |  | 5 (12.20) |  |
AJCC N, n (%) | Â | Â | Â | Â | Â | Â |
 N0 | 458 (73.05) | 316 (72.64) | 142 (73.96) | 0.732 | 27 (65.85) | 0.317 |
 N1-3 | 169 (26.95) | 119 (27.36) | 50 (26.04) |  | 14 (34.15) |  |
AJCC M, n (%) | Â | Â | Â | Â | Â | Â |
 M0 | 563 (89.79) | 389 (89.43) | 174 (90.62) | 0.647 | 37 (90.24) | 0.926 |
 M1 | 64 (10.21) | 46 (10.57) | 18 (9.38) |  | 4 (9.76) |  |
Grade | Â | Â | Â | Â | Â | Â |
 I | 8 (1.28) | 7 (1.61) | 1 (0.52) | 0.752 | 0 (0.00) | 0.001 |
 II | 15 (2.39) | 11 (2.53) | 4 (2.08) |  | 0 (0.00) |  |
 III | 94 (14.99) | 67 (15.40) | 27 (14.06) |  | 0 (0.00) |  |
 IV | 349 (55.66) | 237 (54.48) | 112 (58.33) |  | 0 (0.00) |  |
 Unknown | 161 (25.68) | 113 (25.98) | 48 (25.00) |  | 41 (100.00) |  |
Surgery | Â | Â | Â | Â | Â | Â |
 None | 17 (2.71) | 10 (2.30) | 7 (3.65) | 0.430 | 1 (2.44) | 0.086 |
 Local excision | 353 (56.30) | 241 (55.40) | 112 (58.33) |  | 16 (39.02) |  |
 Complete cystectomy | 257 (40.99) | 184 (42.30) | 73 (38.02) |  | 24 (58.54) |  |
Lymph node ratio | Â | Â | Â | Â | Â | Â |
 None, Biopsy | 372 (59.33) | 254 (58.39) | 118 (61.46) | 0.590 | 21 (51.22) | 0.567 |
 < 0.061 | 123 (19.62) | 90 (20.69) | 33 (17.19) |  | 9 (21.95) |  |
 ≥ 0.061 | 132 (21.05) | 91 (20.92) | 41 (21.35) |  | 11 (26.83) |  |
Radiotherapy | Â | Â | Â | Â | Â | Â |
 Yes | 70 (11.16) | 44 (10.11) | 26 (13.54) | 0.209 | 4 (9.76) | 0.781 |
 No | 557 (88.84) | 391 (89.89) | 166 (86.46) |  | 37 (90.24) |  |
Chemotherapy | Â | Â | Â | Â | Â | Â |
 Yes | 298 (47.53) | 206 (47.36) | 92 (47.92) | 0.897 | 10 (24.39) | 0.004 |
 No | 329 (52.47) | 229 (52.64) | 100 (52.08) |  | 31 (75.61) |  |
Tumor size (mm) | Â | Â | Â | Â | Â | Â |
 ≤ 31.5 | 173 (27.59) | 126 (28.97) | 47 (24.48) | 0.508 | 11 (26.83) | 0.990 |
 > 31.5 | 208 (33.18) | 141 (32.41) | 67 (34.90) |  | 14 (34.15) |  |
 Unknown | 246 (39.23) | 168 (38.62) | 78 (40.62) |  | 16 (39.02) |  |