Table 4.
Comparison of diagnostic performance of US category and combined US category with SWE parameters
| Variable | Sensitivity | Specificity | PPV | NPV | Accuracy |
|---|---|---|---|---|---|
| US category | 95.12 (39/41) | 85.19 (46/54) | 82.98 (39/47) | 95.83 (46/48) | 89.47 (85/95) |
| US category+Emax (combination) | 100 (41/41) | 85.19 (46/54) | 83.67 (41/49) | 100 (46/46) | 91.58 (87/95) |
| US category+Emean (combination) | 97.56 (40/41) | 87.04 (47/54) | 85.11 (40/47) | 97.92 (47/48) | 91.58 (87/95) |
| US category+Emin (combination) | 97.56 (40/41) | 88.89 (48/54) | 86.96 (40/46) | 97.96 (48/49) | 92.63 (88/95) |
| P-value | P-value | P-value | P-value | P-value | |
| US category vs. US category+Emax | 0.47 | 1.0 | 0.85 | 0.49 | 0.80 |
| US category vs. US category+Emean | 1.0 | 0.99 | 0.99 | 0.99 | 0.80 |
| US category vs. US category+Emin | 1.0 | 0.77 | 0.81 | 0.98 | 0.61 |
| US category vs. US category+Eratio | 1.0 | 1.0 | 0.82 | 0.99 | 0.99 |
Values are presented as percent (number).
US, ultrasound; SWE, shear wave elastography; PPV, positive predictive value; NPV, negative predictive value; Emax, maximum pixel value for a region of interest (ROI); Emean, mean value for a 2-mm diameter ROI placed in the stiffest region; Emin, minimum pixel value for a ROI; Eratio, the ratios of mean stiffness for the lesion-to-normal parenchyma.