Table 3.

Sensitivity, specificity, positive predictive value (PPV), positive negative value (PNV), accuracy and likelihood ratio of the four diagnostic modalities applied in group B.

Indicator	NBI	WLE 1 + 2	WLE 2	WLE 1 + 2 and NBI
Sensitivity	82.4 %	88.3 %	64.7 %	76.5 %
Specificity	94.1 %	29.4 %	85.3 %	94.1 %
PPV	87.5 %	38.4 %	68.7 %	86.7 %
NPV	91.4 %	83.3 %	82.8 %	88.9 %
Accuracy	90.2 %	49.0 %	78.4 %	88.2 %
Positive likelihood ratio	13.96	1.25	4.40	12.97
Negative likelihood ratio	0.18	0.40	0.41	0.25
Mode	Area	Lower limit 95% CI	Upper limit 95% CI	p
NBI	0.88	0.78	0.98	<0.0001
WLE 1 + 2	0.58	0.47	0.69	<0.0001
WLE 2	0.75	0.62	0.88	<0.0001
WLE 1 + 2 and NBI	0.85	0.74	0.96	<0.0001
Mode comparison	z	Lower limit 95% CI	Upper limit 95% CI	p
WLE 1 + 2 vs. WLE 2	−2.365	0.347	−0.296	0.018
WLE 1 + 2 vs. NBI	−3.714	0.330	−0.449	<0.0001
WLE 1 + 2 vs. WLE + NBI	−3.674	0.335	−0.406	<0.0001
WLE 2 vs. NBI	−1.842	0.342	−0.273	0.066
WLE 2 vs. WLE + NBI	−1.532	0.348	−0.235	0.126
NBI vs. WLE + NBI	1.000	0.322	−0.028	0.317

CI: confidence interval; NBI: narrow band imaging; NPV: negative predictive value; PPV: positive predictive value; WLE: white light endoscopy.