Table 3. Diagnostic performances of the mean homogeneity indices obtained from the 12 ROIs for discriminating pleomorphic adenomas from normal parotid parenchyma.
| ROI size (mm2) | Optimal cutoff values | AUC ± SE (95% CI) | Sensitivities (95% CI) | Specificities (95% CI) | PPV (%) | NPV (%) | ACC (%) |
|---|---|---|---|---|---|---|---|
| 9 | 0.07 | 0.944±0.024 (0.876–0.981) | 83.8 (68.0–93.8) | 92.9 (82.7–98.0) | 88.6 | 89.7 | 89.3 |
| 28 | W0.11 | 0.955±0.022 (0.891–0.987) | 89.2 (74.6–97.0) | 91.1 (80.4–97.0) | 86.9 | 92.7 | 90.3 |
| 34 | 0.11 | 0.954±0.022 (0.890–0.987) | 83.8 (68.0–93.8) | 96.4 (87.7–99.6) | 93.9 | 90.0 | 91.4 |
| 50 | 0.13 | 0.954±0.021 (0.890–0.987) | 91.9 (78.1–98.3) | 91.1 (80.4–97.0) | 87.2 | 94.5 | 91.4 |
| 60 | 0.14 | 0.952±0.020 (0.887–0.986) | 91.9 (78.1–98.3) | 91.1 (80.4–97.0) | 87.2 | 94.5 | 91.4 |
| 82 | 0.16 | 0.949±0.021 (0.882–0.984) | 91.9 (78.1–98.3) | 87.5 (75.9–94.8) | 82.9 | 94.2 | 89.3 |
| 93 | 0.17 | 0.945±0.022 (0.878–0.982) | 91.9 (78.1–98.3) | 85.7 (73.8–93.6) | 80.9 | 94.1 | 88.2 |
| 98 | 0.16 | 0.943±0.023 (0.874–0.980) | 89.2 (74.6–97.0) | 87.5 (75.9–94.8) | 82.5 | 92.5 | 88.2 |
| 115 | 0.17 | 0.930±0.027 (0.857–0.972) | 89.2 (74.6–97.0) | 87.5 (75.9–94.8) | 82.5 | 92.5 | 88.2 |
| 130 | 0.16 | 0.925±0.029 (0.852–0.970) | 83.8 (68.0–93.8) | 94.6 (85.1–98.9) | 91.1 | 89.8 | 90.3 |
| 136 | 0.16 | 0.922±0.031 (0.847–0.967) | 83.8 (68.0–93.8) | 94.6 (85.1–98.9) | 91.1 | 89.8 | 90.3 |
| 149 | 0.16 | 0.915±0.034 (0.839–0.963) | 83.8 (68.0–93.8) | 94.6 (85.1–98.9) | 91.1 | 89.8 | 90.3 |
ROC, receiver operating characteristic curve; AUC, area under curve; ADC, apparent diffusion coefficient; SE, standard error; CI, confidence interval; ROI, region of interest; PPV, positive predictive value; NPV, negative predictive value; ACC, accuracy.