Table 1.
Clinical-radiological features of the training and test sets.
| Clinical-radiological features | Training set (n = 218) | Test set (n = 94) | ||||
|---|---|---|---|---|---|---|
| BPTs (n = 143) | MPTs (n = 75) | p-value | BPTs (n = 62) | MPTs (n = 32) | p-value | |
| Gendera (M/F) | 75/68 | 39/36 | 0.950 | 37/25 | 17/15 | 0.543 |
| Ageb (year) | 55.00 (15.00) | 48.00 (24.50) | 0.023 | 53.69 (14.34) | 51.38 (16.54) | 0.483 |
| Smokea (absent/present) | 81/62 | 47/28 | 0.391 | 34/28 | 21/11 | 0.315 |
| Sizeb (mm) | 19.77 (8.43) | 23.09 (12.01) | 0.003 | 20.84 (8.46) | 28.83 (14.70) | 0.001 |
| Locationa (superficial/deep lobe) | 111/32 | 50/25 | 0.080 | 57/5 | 16/16 | <0.001 |
| Scopea (localized/diffuse) | 143/0 | 65/10 | <0.001 | 62/0 | 23/9 | <0.001 |
| Numbera (single/multiple) | 136/7 | 73/2 | 0.669 | 59/3 | 31/1 | 1.000 |
| Shapea (regular/irregular) | 96/47 | 36/39 | 0.006 | 51/11 | 14/18 | <0.001 |
| Margina (well-defined/ill-defined) | 123/20 | 44/31 | <0.001 | 57/5 | 17/15 | <0.001 |
| CNAa (absent/present) | 77/66 | 39/36 | 0.795 | 42/20 | 23/9 | 0.681 |
| ISTa (absent/present) | 137/6 | 44/31 | <0.001 | 57/5 | 17/15 | <0.001 |
| LMa (absent/present) | 143/0 | 68/7 | 0.001 | 62/0 | 28/4 | 0.021 |
| CT valueb (HU) | ||||||
| Plain | 42.00 (15.00) | 45.00 (16.50) | 0.524 | 43.15 (11.94) | 43.97 (13.26) | 0.761 |
| Arterial | 84.00 (41.00) | 79.00 (38.50) | 0.591 | 86.69 (36.32) | 84.31 (26.36) | 0.743 |
| Venous | 86.00 (29.00) | 87.00 (31.50) | 0.961 | 86.94 (23.71) | 89.50 (26.85) | 0.636 |
| Art-Pl | 38.00 (36.50) | 34.00 (30.00) | 0.209 | 34.00 (39.50) | 33.00 (24.75) | 0.886 |
| Ven-Art | 3.07 (23.72) | 5.03 (18.21) | 0.499 | 6.00 (28.75) | 8.00 (16.75) | 0.330 |
a
Categorical data as numbers (n).
b
Quantitative data are mean (standard deviation) or median (quartile). p-value was calculated with independent samples t-test or Mann–Whitney U test. p-value was calculated with the χ2 or Fisher’s exact test. BPTs, benign parotid tumors; MPTs, malignant tumors; F, female; M, male; CNA, cystic or necrotic areas; LM, lymphatic metastasis; CT, computed tomography; Art, arterial phase; Pl, plain scan; Ven, venous phase.