METHODS	In-hospital patients who were candidates for colonoscopy were randomly assigned to : group 1 single-dose ( PEG 4L the day before the study , n = 60 ) ; group 2 : split-dose ( 2L the day before and 2L on the day of the procedure , n = 61 ) ; and group 3 : low-volume 2-L PEG solution ( the day of the procedure , n = 59 ) .\