Biopsy forceps are useful for measuring esophageal varices in vitro

Table 1 Demographic characteristics of participants

Participants’ characteristics	n (%)
No. of participants	52
Practice setting (all)	52
Academic	48 (92.3)
Private	4 (7.7)
Age, yr (mean, SD)	39.9 (6.6)
Gender (male)	26 (50)
Years in practice (mean, SD)	11.0 (6.9)
No. of gastroscopies/year
< 500	15 (28.9)
501-1000	9 (17.3)
1001-1500	5 (9.6)
1501-2000	7 (13.5)
> 2000	16 (30.8)

Table 2 Measurement accuracy of 52 endoscopists for each measurement condition

	Visual method	Biopsy forceps	P value
All varices
Accuracy (exact)	13.81%	20.28%	0.004
Actual size ≤ 5 mm
Accuracy (exact)	22.12%	34.62%	0.005
Actual size > 5 mm
Accuracy (exact)	9.07%	12.09%	0.185
Correct classification
≤ 5 mm (category A)	84.62%	87.98%	0.996
> 5 mm (category B)	64.56%	78.85%	< 0.0001

Table 3 Comparison of actual versus estimated varices size using a visual estimation method and open biopsy forceps method

	Actual size ≤ 5 mm (4 varices)	Actual size > 5 mm (7 varices)
Visual method
Size estimate ≤ 5 mm	176	129
Size estimate > 5 mm	32	235
Accuracy	84.62%	64.56%
Biopsy forceps
Size estimate ≤ 5 mm	183	77
Size estimate > 5 mm	25	287
Accuracy	87.98%	78.85%

Values are total number of measurements, including 11 simulated varices by 52 endoscopists. Overall accuracy = 71.85% using visual method (accurate measurements shown in bold).Overall accuracy = 82.17% using biopsy forceps method (accurate measurements shown in bold).