Endoscopic Detection of Early Esophageal Squamous Cell Carcinoma in Patients with Achalasia: Narrow-Band Imaging versus Lugol's Staining

Table 2

Comparison of the performance across methods (95% confidence interval) (%).

	Conventional examination	Narrow-band imaging	Lugol’s
Sensitivity	100 (100-100)	100 (100-100)	100 (100-100)
Specificity	100 (100-100)	85.7 (75.1–96.3)	81 (69.1–92.8)
PPV	100 (100-100)	14.3 (−11.6–40.2)	11.1 (−9.4–31.6)
NPV	100 (100-100)	100 (100-100)	100 (100-100)
Accuracy	100 (100-100)	86 (75.7–96.4)	81.4 (69.8–93)
PLR	n/c	7	5.3
NLR	0	0	0

PPV: positive predictive value; NPV: negative predictive value; PLR: positive likelihood ratio; NLR: negative likelihood ratio; n/c: non calculable.