Table 1 Relationship between clinical and US characteristics, and CNM of patients in the modeling and validation groups.
Modeling | Total | CNM(−) | CNM(+) | P value | Validation Total | CNM(−) | CNM(+) | P value |
|---|---|---|---|---|---|---|---|---|
N = 1918 | N = 1062 | N = 856 | N = 944 | N = 560 | N = 384 | |||
Gender | Â | Â | Â | <0.001 | Â | Â | Â | <0.001 |
    Male | 384 (20.0%) | 166 (15.6%) | 218 (25.5%) |  | 165 (17.2%) | 74 (13.2%) | 91 (23.7%) |  |
    Female | 1534 (80.0%) | 896 (84.4%) | 638 (74.5%) |  | 779 (82.5%) | 486 (86.8%) | 293 (76.3%) |  |
Age | Â | Â | Â | <0.001 | Â | Â | Â | <0.001 |
    ≤40 years | 838 (43.7%) | 365 (34.4%) | 473 (55.3%) |  | 375 (39.7%) | 169 (30.2%) | 206 (53.6%) |  |
    >40 years | 1080 (56.3%) | 697 (65.6%) | 383 (44.7%) |  | 569 (60.3%) | 391 (69.8%) | 178 (46.4%) |  |
Tumor size | Â | Â | Â | <0.001 | Â | Â | Â | <0.001 |
    ≤1 cm | 1169 (61.0%) | 793 (74.7%) | 376 (43.9%) |  | 582 (61.7%) | 419 (74.8%) | 163 (42.4%) |  |
    1–2 cm | 530 (27.6%) | 211 (19.9%) | 319 (37.3%) |  | 273 (28.9%) | 118 (21.1%) | 155 (40.4%) |  |
    2–3 cm | 163 (8.5%) | 51 (4.8%) | 112 (13.1%) |  | 59 (6.3%) | 19 (3.4%) | 40 (10.4%) |  |
    >3 cm | 56 (2.9%) | 7 (0.6%) | 19 (5.7%) |  | 30 (3.2%) | 4 (0.7%) | 26 (6.8%) |  |
Microcalcification | Â | Â | Â | <0.001 | Â | Â | Â | <0.001 |
    No | 733 (38.2%) | 469 (44.2%) | 264 (30.8%) |  | 345 (36.5%) | 239 (42.7%) | 106 (27.6%) |  |
    Scattered distribution | 966 (50.4%) | 491 (46.2%) | 475 (55.5%) |  | 470 (49.8%) | 254 (45.4%) | 216 (56.3%) |  |
    Aggregated distribution | 219 (11.4%) | 102 (9.6%) | 117 (13.7%) |  | 129 (13.7%) | 67 (12.0%) | 62 (16.1%) |  |
Shape | Â | Â | Â | 0.899 | Â | Â | Â | 0.124 |
    Normal | 450 (23.5%) | 248 (23.4%) | 202 (23.6%) |  | 224 (23.7%) | 123 (22.0%) | 101 (26.3%) |  |
    Abnormal | 1468 (76.5%) | 814 (76.6%) | 654 (76.4%) |  | 720 (76.3%) | 437 (78.0%) | 283 (73.7%) |  |
Internal blood supply | Â | Â | Â | <0.001 | Â | Â | Â | 0.002 |
    Not rich | 1484 (77.4%) | 858 (80.8%) | 626 (73.1%) |  | 726 (76.9%) | 450 (80.4%) | 276 (71.9%) |  |
    Rich | 434 (22.6%) | 204 (19.2%) | 230 (26.9%) |  | 218 (23.1%) | 110 (19.6%) | 108 (18.1%) |  |
Internal blood vessels | Â | Â | Â | 0.737 | Â | Â | Â | 0.104 |
    Normal | 1614 (84.2%) | 891 (83.9%) | 723 (84.5%) |  | 802 (85.0%) | 467 (83.4%) | 335 (87.2%) |  |
    Abnormal | 304 (15.8%) | 171 (16.1%) | 133 (15.5%) |  | 142 (15.0%) | 93 (16.6%) | 49 (12.8%) |  |
RI > 0.7 |  |  |  | <0.001 |  |  |  | 0.002 |
    No | 1494 (77.9%) | 878 (82.7%) | 616 (72.0%) |  | 746 (79.0%) | 462 (82.5%) | 284 (74.0%) |  |
    Yes | 424 (22.1%) | 184 (17.3%) | 240 (28.0%) |  | 198 (21.0%) | 98 (17.5%) | 100 (26.0%) |  |
Multiple nodular lesions | Â | Â | Â | 0.039 | Â | Â | Â | 0.018 |
    No | 730 (38.1%) | 426 (40.1%) | 304 (35.5%) |  | 342 (36.2%) | 220 (39.3%) | 122 (31.8%) |  |
    Yes | 1188 (61.9%) | 636 (59.9%) | 552 (64.5%) |  | 602 (63.8%) | 340 (60.7%) | 262 (68.2%) |  |
Hashimoto’s disease |  |  |  | 0.926 |  |  |  | 0.001 |
    No | 1284 (66.9%) | 710 (66.9%) | 574 (67.1%) |  | 858 (90.9%) | 536 (95.7%) | 322 (83.9%) |  |
    Yes | 634 (33.1%) | 352 (33.1%) | 282 (32.9%) |  | 86 (9.1%) | 24 (4.3%) | 62 (16.1%) |  |
Extrathyroid extension | Â | Â | Â | <0.001 | Â | Â | Â | <0.001 |
    No | 1743 (90.9%) | 1020 (96.0%) | 723 (84.5%) |  | 858 (90.9%) | 536 (95.7%) | 322 (83.9%) |  |
    Yes | 175 (9.1%) | 42 (4.0%) | 133 (15.5%) |  | 86 (9.1%) | 24 (4.3%) | 62 (16.1%) |  |
