Prospective randomized controlled trial of oral sodium phosphate and polyethylene glycol lavage in bowel preparation for colonoscopy

INTERVENTION: Niflec(polyethylene glycol lavage) group 1) 10ml Laxoberon Solution is administered orally at bedtime 2) Patients are instructed to drink only clear liquids after dinner 3) At our endscopy unit, patient should drink 2L polyethylene glycol lavage (Niflec) at the speed of about 200ml for every ten minutes from beginning time (10:00 a.m.) Visiclear(oral phosphate tablets) group 1) 10ml Laxoberon Solution is administered orally at bedtime 2) Patients are instructed to drink only clear liquids after dinner 3) At our endoscopy unit, patient should take 40 sodium phosphate tablets (Visiclear tablets) in divided doses (take as 5 tablets every 15 minutes with 200mL of clear liquids [water or tea]) from beginning time (10:00 a.m.) CONDITION: Patients scheduled for colonoscopy PRIMARY OUTCOME: To evaluate detection rates of polyps smaller than 5mm SECONDARY OUTCOME: To evaluate detection rates of all prominent lesions and diverticula; To evaluate blood pressure and pulse rates of patients before and after; colonoscopy INCLUSION CRITERIA: Patients who fills everything the following 1) Patients scheduled for colonoscopy in our hospital 2) Age of patients is from 20 to 75 years old 3) Patients who were able to provide written informed consent for participation in this study 4) Outpatient and in‐patient