Narrow band imaging and white light endoscopy in the characterization of a polypectomy scar: A single-blind observational study

Table 3 Diagnostic performance of white light endoscopy and narrow band imaging for each group

	WLE-NBI group			NBI-WLE group
	WLE (95%CI)	NBI (95%CI)		NBI (95%CI)	WLE (95%CI)
Sensitivity	78.9% (56.7-91.5)	89.5% (68.6-97.1)		85.0% (64.0-94.8)	80.0% (58.4-91.9)
Specificity	84.2% (69.6-92.6)	84.2% (69.6-92.6)		77.1% (61.0-87.9)	82.9% (67.3-91.9)
False positive	15.8% (7.4-30.4)	15.80% (7.4-30.4)		22.9% (12.1-39.0)	17.1% (8.1-32.7)
False negative	21.1% (8.5-43.3)	10.50% (2.9-31.4)		15.00% (5.2-36.0)	20.0% (8.1-41.6)
PPV	71.4% (50.0-86.2)	73.9% (53.5-87.5)		68.0% (48.4-82.8)	72.7% (51.8-86.8)
NPV	88.9% (74.7-95.6)	94.1% (80.9-98.4)		90.0% (74.4-96.5)	87.9% (72.7-95.2)
LR +	5 (2.3-10.8)	5.7 (2.7-12.0)		3.7 (2.0-7.0)	4.7 (2.2-10.0)
LR -	0.3 (0.1-0.6)	0.1 (0.03-0.5)		0.2 (0.1-0.6)	0.2 (0.1-0.6)
Global accuracy	82.5% (70.6-90.2)	86.0% (74.7-92.7)		80.0% (67.6-88.4)	81.8% (69.7-89.8)
AUC	81.6% (70.5-92.7)	86.8% (77.6-96.0)	P = 0.15	81.1% (70.4-91.8)	81.4% (70.4-92.4)	P = 0.9

CI: Confidence interval; WLE: White light endoscopy; NBI: Narrow band imaging; PPV: Positive predictive value; NPV: Negative predictive value; LR: Likelihood ratio; AUC: Area under the curve.