Table 3.

Corvis ST parameters with AUC > 0.6 in distinguishing subclinical keratoconus corneas from normal ones

Variable	AUC (95% CI)	Optimal threshold	Sensitivity	Specificity	Youden index	Significance level P (Area = 0.5)
ARTh	0.813 (0.740, 0.874)	≤ 488.1	78.08%	79.71%	0.5779	< 0.0001
CBI	0.804 (0.729, 0.866)	> 0.47	78.08%	71.01%	0.4910	< 0.0001
TBI	0.858 (0.790, 0.911)	> 0.33	78.08%	76.81%	0.5489	< 0.0001
DA ratio	0.632 (0.547, 0.711)	> 4.1	73.97%	47.83%	0.2180	0.0048
SPA1	0.602 (0.516, 0.683)	≤ 106.8	84.93%	33.33%	0.1826	0.0321

AUC Area under the curve, CI Confidence interval, ARTh Ambrósio relational thickness to the horizontal profile, CBI Corvis biomechanical index, TBI Tomographic and biomechanical index, DA Deformation amplitude, SPA1 Stiffness parameter at the first applanation