Evaluation of the HB&L System for the Microbiological Screening of Storage Medium for Organ-Cultured Corneas

Table 2

Sensitivity, specificity, predictive values and likelihood ratios.

Parameters	Formula	Value (95% CI)
Sensitivity (Se) (%)	TP(TP+FN)	95.5 (90.4–98.3)
Specificity (Sp) (%)	TN(TN+FP)	99.9 (99.8–99.9)
Positive predictive value (PPV) (%)	Se×CSe×C+1−Sp×(1−C)	96.2 (93.7–97.9)
Negative predictive value (NPV) (%)	Sp×(1−C)Sp×(1−C)+(1−Se)×C	99.8 (99.7–99.9)
Positive likelihood ratio (LR+)	Se1−Sp	717.7 (424.6–1212.9)
Negative likelihood ratio (LR−)	1−SeSp	0.05 (0.02–0.10)

TP: true positive; FN: false negative; FP: false positive; C: prevalence.