Table 1.
Univariate analysis of data collected from patients included in training and test sets
| Classification | Training set (n = 2274) | Test set (n = 2274) | P-value* |
|---|---|---|---|
| Clinical Characters | |||
| Male (%) | 58.9 | 55.5 | 0.051 |
| Age (years) | 57.97 | 58.28 | 0.395 |
| Diameter of lesion (cm) | 1.96 | 1.95 | 0.450 |
| Smoking history (%) | 42.5 | 51.5 | 0.576 |
| Smoking quantity pieces-year | 462.7 | 473.6 | 0.615 |
| Previous history of malignant tumor (%) | 3.9 | 3.0 | 0.154 |
| Family cancer history (%) | 13.9 | 13.5 | 0.763 |
| Biomarker results | |||
| NSE (ng/mL) | 11.40 | 11.64 | 0.181 |
| CEA (ng/mL) | 6.79 | 6.71 | 0.114 |
| CYFRA 21-1 (ng/mL) | 2.62 | 2.59 | 0.387 |
| CA125 (ng/mL) | 16.95 | 16.76 | 0.883 |
| SCC (ng/mL) | 0.819 | 0.829 | 0.618 |
| Histological diagnosis malignant (%) | 77.2 | 77.7 | 0.741 |
| CT scan findings | |||
| Clear border (%) | 9.4 | 9.9 | 0.640 |
| Satellite lesions (%) | 2.9 | 3.2 | 0.689 |
| Cavity (%) | 3.9 | 4.5 | 0.388 |
| Lobulation (%) | 37.0 | 38.5 | 0.393 |
| Spiculation (%) | 42.7 | 41.9 | 0.675 |
| Calcification (%) | 5.9 | 6.1 | 0.827 |
| Pleura retraction sign (%) | 3.9 | 3.8 | 0.788 |
| Position of SPN | |||
| LUL (%) | 23.6 | 28.1 | 0.004 |
| LLL (%) | 16.1 | 17.5 | 0.310 |
| RUL (%) | 30.7 | 29.7 | 0.573 |
| RML (%) | 7.2 | 5.2 | 0.018 |
| RLL (%) | 22.4 | 19.6 | 0.051 |
*Univariate analysis: t-tests and chi-squared test were performed for proportional differences or mean differences in variables between training set and test set. CA, carbohydrate antigen; CEA, carcinoembryonic antigen; CT, computed tomography; CYRFA 21-1, cytokeratin 19-fragment marker; LLL, left lower lobe; LUL, left upper lobe; NSE, neuron-specific enolase; RLL, right lower lobe; RML, right middle lobe; RUL, right upper lobe; SCC, squamous cell carcinoma; SPN, solitary pulmonary nodule.