Table 5. Coordinates of the receiver operating characteristic (ROC) curve.
| Positive if Greater Than or Equal Toa | Sensitivity | 1—Specificity | Specificity | Youden Index |
|---|---|---|---|---|
| 6 | 1 | 1 | 0 | 0 |
| 7.5 | 0.95 | 0.9 | 0.1 | 0.05 |
| 8.5 | 0.921 | 0.87 | 0.13 | 0.051 |
| 9.5 | 0.901 | 0.82 | 0.18 | 0.081 |
| 10.5 | 0.861 | 0.8 | 0.2 | 0.061 |
| 11.5 | 0.851 | 0.71 | 0.29 | 0.141 |
| 12.5 | 0.842 | 0.66 | 0.34 | 0.182 |
| 13.5 | 0.802 | 0.49 | 0.51 | 0.312 |
| 14.5 | 0.762 | 0.36 | 0.64 | 0.402 |
| 15.5 | 0.713 | 0.3 | 0.7 | 0.413 |
| 16.5 | 0.673 | 0.26 | 0.74 | 0.413 |
| 17.5 | 0.634 | 0.22 | 0.78 | 0.414 |
| 18.5 | 0.545 | 0.17 | 0.83 | 0.375 |
| 19.5 | 0.535 | 0.14 | 0.86 | 0.395 |
| 20.5 | 0.475 | 0.11 | 0.89 | 0.365 |
| 21.5 | 0.436 | 0.11 | 0.89 | 0.326 |
| 22.5 | 0.406 | 0.11 | 0.89 | 0.296 |
| 23.5 | 0.386 | 0.06 | 0.94 | 0.326 |
| 24.5 | 0.337 | 0.03 | 0.97 | 0.307 |
| 25.5 | 0.287 | 0.03 | 0.97 | 0.257 |
The best cut-off point was considered that at which the closest number of J = +1 was obtained in the Youden Index (J)