Table 1. Clinical information for the training and test sets.
| Clinical features | Training set | Test set | |||||||
|---|---|---|---|---|---|---|---|---|---|
| All | Benign | Malignant | P value | All | Benign | Malignant | P value | ||
| Maximum diameter (mm) | 17.83±10.71 | 15.21±7.07 | 23.68±14.55 | <0.001 | 17.68±7.61 | 15.87±7.00 | 20.78±7.69 | <0.001 | |
| Age (years) | 45.95±15.78 | 40.49±13.40 | 58.13±13.81 | <0.001 | 46.85±14.90 | 41.86±14.36 | 55.40±11.66 | <0.001 | |
| Calcification | <0.001 | <0.001 | |||||||
| None | 192 (0.72) | 152 (0.83) | 40 (0.49) | 96 (0.84) | 67 (0.93) | 29 (0.69) | |||
| Yes | 73 (0.28) | 31 (0.17) | 42 (0.51) | 18 (0.16) | 5 (0.07) | 13 (0.31) | |||
| CDFI | <0.001 | <0.001 | |||||||
| None | 162 (0.61) | 136 (0.74) | 26 (0.32) | 83 (0.73) | 62 (0.86) | 21 (0.50) | |||
| Yes | 103 (0.39) | 47 (0.26) | 56 (0.68) | 31 (0.27) | 10 (0.14) | 21 (0.50) | |||
| BI-RADS | <0.001 | <0.001 | |||||||
| 3–4a | 220 (0.83) | 177 (0.97) | 43 (0.52) | 72 (0.63) | 64 (0.89) | 8 (0.19) | |||
| 4b–5 | 45 (0.17) | 6 (0.03) | 39 (0.48) | 42 (0.37) | 8 (0.11) | 34 (0.81) | |||
Continuous data are presented as the mean ± standard deviation; categorical data are presented as number (ratio). BI-RADS category was determined by an ultrasound diagnostic physician. CDFI, color Doppler flow imaging; BI-RADS, Breast Imaging Reporting and Data System.