Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience

Table 4 Diagnostic performances of the eleven endoscopists in predicting polyp histology subdivided according to level of experience, location, size, morphology and image quality

	Sensitivity	Specificity	Accuracy	PPV1	NPV1
Overall	79.3 ± 7.0	85.7 ± 9.6	81.1 ± 4.7	84.7	80.5
Experience
GE	76.4 ± 6.6	82.1 ± 9.2	78.0 ± 3.7	81.0	77.7
Trainees	81.0 ± 7.1	87.8 ± 9.9	82.9 ± 4.5	86.9	82.2
P value	0.320	0.378	0.098
Location
Proximal	74.6 ± 30.9	80.0 ± 29.7	75.6 ± 30.1	78.9	75.9
Distal	84.2 ± 29.0	88.9 ± 8.8	86.0 ± 23.4	88.4	84.9
P value	0.353	0.547	0.187
Size
Diminutive	63.2 ± 33.3	90.2 ± 7.8	74.2 ± 29.1	86.6	71.0
Non-diminutive	97.2 ± 7.2	27.32	93.1 ± 18.3	57.2	90.7
P value	< 0.001		0.008
Morphology
Polypoid	81.8 ± 25.1	85.1 ± 20.0	83.1 ± 23.0	84.6	82.4
Non-polypoid	75.4 ± 35.0	87.9 ± 13.9	77.3 ± 32.8	86.2	78.1
P value	0.536	0.829	0.470
Image quality
Excellent	89.3 ± 23.1	93.5 ± 6.9	90.3 ± 20.3	93.2	89.7
Good	63.6 ± 33.3	77.9 ± 23.4	68.4 ± 30.5	74.2	68.2
P value	0.010	0.117	0.007

Data are expressed as mean ± SD.

¹Based on our sensitivity and specificity data and literature data regarding prevalences of non-adenomatous and adenomatous polyps;

²Based on 1 case only, no statistics performed. GE: Gastroenterologist; PPV: Positive predictive value; NPV: Negative predictive value.