Efficacy of premedication with activated Dimethicone or N-acetylcysteine in improving visibility during upper endoscopy

Table 1 Demographic characteristics of patients in each group

Group	A	B	C	D
Number	38	37	37	36
Age(yr; mean ± SD)	42.2 ± 13.9	44.3 ± 18.0	44.6 ± 16.4	41.8 ± 17.5
Female: Male (n)	18:20	19:18	16:21	18:18
Cause of endoscopy
Dyspepsia	25	28	21	23
Reflux	6	5	4	4
Screening for cancer	7	0	5	4
Others	0	4	7	5

No significant difference between each two groups regarding age and gender. Group A received water, group B received activated Dimethicone plus water, group C received N-acetylcysteine plus water, and group D received activated Dimethicone and N-acetylcysteine plus water.

Table 2 The mean rank¹ of any group of patients in distinct domains of stomach

Group	A	B	C	D
Antrum	102.82	48.91	91.74	53.19
Lower part of the greater curvature	103.43	51.24	88.00	53.99
Upper part of the greater curvature	100.17	48.49	92.43	55.71
Fundus	102.21	51.43	90.96	52.04

¹The lower the mean rank, the better the visibility.