Does hyoscine butylbromide really improve polyp detection during colonoscopy? A meta-analysis of randomized controlled trials

Table 1 Quality analysis of included trials

Study	Randomization method	Allocation concealment	Blinding	Withdrawals	Jadad score
Byun et al[20]	Not mentioned	Unclear	Double-blind	Not mentioned	3
Lee et al[21]	Computer-generated	Adequate	Double-blind	Not mentioned	6
Corte et al[10]	Computer-generated	Adequate	Double-blind	Described	7
de Brouwer et al[15]	Not mentioned	Unclear	Double-blind	Described	4
Rondonotti et al[16]	Computer-generated	Adequate	Double-blind	Described	7

Table 2 Baseline characteristics of included trials in the meta-analysis

Study	Group	Age	Gender	Intervention	Time of intervention	Bowel preparation	Colonoscopy staff	Sedation
			(M/F)
Byun et al[20]	Hyoscine butylbromide	Not mentioned	103 (total number)	20 mg, iv	At the time of colonoscopic withdrawal	Not mentioned	Not mentioned	Not mentioned
	Placebo		102 (total number)	1 mL NS, iv
Lee et al[21]	Hyoscine butylbromide	59.4 ± 8.5	27/31	20 mg, iv	When the scope reached the cecum	Polyethylene glycol solution	A single experienced endoscopist	Midazolam, 3-5 mg, iv
	Placebo	58.4 ± 7.9	23/35	1 mL NS, iv
Corte et al[10]	Hyoscine butylbromide	60.6 ± 11.2	162/141	20 mg, iv	After the cecum was reached	PrepKit C; picoPrep; moviPrep; glycoPrep	8 endoscopists, 14 fellows	Midazolam, fentanyl with or without propofol, iv
	Placebo	61.4 ± 10.4	157/141	1 mL NS, iv
de Brouwer et al[15]	Hyoscine butylbromide	61.5	156/184	20 mg, iv	When the cecum was reached and the withdrawal of the colonoscope was started	Polyethylene glycol solution	5 gastroenterologists and 3 nurse endoscopists	Not mentioned
	Placebo	61.4	176/158	1 mL NS, iv
Rondonotti et al[16]	Hyoscine butylbromide	57.3 ± 11.5	90/112	20 mg, iv	At cecal intubation	Senna-based preparation	Six board-certified gastroenterologists	Midazolam and pethidine, iv
	Placebo	57.3 ± 13.5	87/113	1 mL NS, iv

Table 3 Characteristics of randomized comparisons of hyoscine butylbromide and placebo groups reported in the literature

Study	Group	Polyp detection rate	Adenoma detection rate	Polyps per patient (n)	Adenomas per patient (n)
Byun et al[20]	Hyoscine butylbromide	45.6%	35.0%	NR	NR
	Placebo	39.2%	29.4%
Lee et al[21]	Hyoscine butylbromide	34.5%	NR	0.9 ± 1.8	NR
	Placebo	25.9%		0.6 ± 1.2
Corte et al[10]	Hyoscine butylbromide	43.6%	27.1%	0.91 ± 0.084	0.55 ± 0.073
	Placebo	36.6%	21.8%	0.70 ± 0.075	0.42 ± 0.062
de Brouwer et al[15]	Hyoscine butylbromide	55.9%	29.7%	1.13	NR
	Placebo	60.2%	31.4%	1.21
Rondonotti et al[16]	Hyoscine butylbromide	38.6%	31.7%	NR	NR
	Placebo	37.0%	28%

NR: Not reported.