Table 4. Cross-validation and diagnostic evaluation results.
| Parameters | Cross-validation |
Diagnostic evaluation |
|||||||||
| Sensitivity | Specificity | LR+ | LR- | AUC | Sensitivity | Specificity | LR+ | LR- | AUC | Cutoff | |
| Normal vs SKCN | |||||||||||
| Pentacam | |||||||||||
| I-S value | 80.6 | 73.08 | 3.00 | 0.27 | 0.863 | 80.1 | 79.2 | 3.84 | 0.25 | 0.862 | >0.44 |
| PRFI | 79.49 | 88.2 | 4.30 | 0.25 | 0.843 | 71.1 | 87.9 | 5.87 | 0.34 | 0.847 | >0.21 |
| Sirius | |||||||||||
| SIb | 70.37 | 91.67 | 7.24 | 0.43 | 0.893 | 86.2 | 84.9 | 5.70 | 0.16 | 0.908 | >0.08 |
| Corvis | |||||||||||
| TBI | 79.49 | 70.81 | 3.64 | 0.30 | 0.818 | 70.8 | 83 | 4.16 | 0.35 | 0.828 | >0.39 |
| Normal vs KCN | |||||||||||
| Pentacam | |||||||||||
| IHD | 90.01 | 100 | NA | 0.10 | 0.9995 | 98.6 | 100 | NA | 0.02 | 0.9995 | >0.02 |
| PRFI | 98.57 | 100 | NA | 0.01 | 0.9997 | 99.2 | 100 | NA | 0.01 | 1.000 | >0.53 |
| Sirius | |||||||||||
| KVb | 92.57 | 100 | NA | 0.07 | 0.9989 | 100 | 98.5 | 53.00 | 0.00 | 0.9991 | >17.50 |
| Corvis | |||||||||||
| TBI | 100 | 94.12 | 17.02 | 0.00 | 0.9998 | 100 | 100 | NA | 0.00 | 1.000 | >0.8 |
I-S value: Inferior-superior difference value; IHD: Index of height decentration; PRFI: Pentacam random forest index; SIb: Symmetry index of back of corneal curvature; KVb: Keratoconus vertex back; TBI: Topographic and biomechanical index; LR±: Positive/negative likelihood ratio; NA: Not available (could not be calculated); AUC: Area under the curve.