Split-dose regimen is recommended for elective colonoscopy because it is associated with higher detection of pre-cancerous polyps and improved colon cleansing. Yet its adoption remains suboptimal. Why?

In a study by Radaelli F et al, 1447 patients undergoing colonoscopy between 8:00 and 14:00 with 4L polyethylene glycol were given the option of split-dose regimen or day-before regimen despite emphasizing the superiority of split-dose regimen on colonoscopy outcomes.

More patients chose the split-dose regimen-61.7%. Consistent with other studies, split-dose regimen was associated with better colon cleansing and polyp detection.

Multivariate analysis showed that colonoscopy appointment before 10:00, travel time to endoscopy center >1 hour, low education level and female gender were inversely correlated with the uptake of split-dose.

Take Home Point: Patients with early morning colonoscopy appointment, longer distance to endoscopy lab, low education status and females are less likely to adopt the split-dose regimen. These patients require additional interventions to increase compliance with the split-dose regimen.


  1. Radaelli F, et al. Barriers against split-dose bowel preparation for colonoscopy. Gut; doi: 10.1136/gutjnl-2015-311049.