Assistant skill in gastric endoscopic submucosal dissection using a clutch cutter

Table 1 Characteristics of the mock lesions treated by endoscopic submucosal dissection with a clutch cutter

	All, n = 32	Expert, (ESD-C-E), n = 16	Non-expert, (ESD-C-NE), n = 16	P value
Location, n (%)				0.72
Middle third	20 (62.5)	9 (56.2)	11 (68.8)
Lower third	12 (37.5)	7 (43.8)	5 (31.2)
Position, n (%)				0.61
Anterior wall	9 (28.1)	4 (25.0)	5 (31.2)
Posterior wall	4 (12.5)	1 (6.2)	3 (18.8)
Greater curvature	19 (59.4)	11 (68.8)	8 (50.0)
Marking size, mm2				0.75
mean ± SD	391.64 ± 288.63	408.54 ± 264.49	374.74 ± 318.76
Median (IQR)	310.86 (184.08-461.78)	314.00 (219.80-515.16)	310.86 (175.84-407.42)

P value was calculated using Fisher’s exact test and the Mann-Whitney U test. ESD: Endoscopic submucosal dissection; ESD-C: ESD using a clutch cutter; ESD-C-E: ESD-C assisted by an expert; ESD-C-NE: ESD-C assisted by a non-expert; IQR: Interquartile range; SD: Standard deviation.