Table 3.
logistic regression of risk factors for PTC.
| β | OR | 95%CI of OR | P value | |
|---|---|---|---|---|
| Age, y (x1) | ||||
| <45 | 0.80 | 2.22 | 1.48–3.35 | 0.000 |
| Echogenicity | ||||
| Hypoechoic | 1.31 | 3.70 | 2.08–6.56 | 0.000 |
| Margin | ||||
| Spiculate | 1.19 | 3.30 | 2.03–5.37 | 0.077 |
| Ill-defined | 0.82 | 2.26 | 0.92–5.58 | 0.000 |
| Border | ||||
| Indefinite | 0.90 | 2.45 | 1.58–3.82 | 0.000 |
| Shape | ||||
| Irregular | 0.76 | 2.13 | 1.28–3.57 | 0.004 |
| Taller than wide | ||||
| Yes | 1.08 | 2.94 | 1.78–4.85 | 0.000 |
| Capsular invasion | ||||
| Yes | 2.05 | 7.76 | 1.82–33.04 | 0.006 |
| Internal composition | ||||
| Solid | 0.90 | 2.46 | 1.42–4.27 | 0.001 |
| Calcification | ||||
| Microcalcification | 1.37 | 3.92 | 2.52–6.09 | 0.000 |
| Macrocalcification | 0.08 | 1.09 | 0.45–2.60 | 0.855 |
| Mixed | 1.76 | 5.84 | 1.67–20.37 | 0.006 |
| Vascularity | ||||
| Central | 0.74 | 2.10 | 1.37–3.21 | 0.001 |
| Cervical lymph nodes | ||||
| Absence of an echogenic hilum | ||||
| Yes | 1.32 | 3.74 | 1.16–12.06 | 0.027 |
| Increased vascularization | ||||
| Yes | 1.27 | 3.55 | 0.84–15.11 | 0.086 |
The model is a stepwise (backward selection) multivariable binary logistic model, applying a 10% significance level for removal. CI –confidence interval; OR – odds ratio.