Split-dose vs same-day bowel preparation for afternoon colonoscopies: A meta-analysis of randomized controlled trials

BACKGROUND

Quality of bowel preparation in afternoon colonoscopies has been a struggle. Currently, a choice of same-day preparation (SaD) or split-dose preparation (SpD) exists; however, randomized controlled trials’ results have varied. 

AIM

To examine the outcomes of SaD and SpD for afternoon colonoscopies.

METHODS

An extensive literature search was conducted using multiple databases. Only randomized controlled trials (RCTs) in adults that compared SaD to SpD with Ottawa bowel preparation score (OBPS) were included. Odds ratio (OR) or mean difference was used to analyze outcomes.

RESULTS

Eleven RCTs were included (n = 1846). No difference was observed for satisfactory bowel preparation based on OBPS among participants receiving SaD vs SpD (OR 0.77; 95%CI: -0.57-1.03; P = 0.07; I² = 5%). Subgroup analysis showed no difference in terms of satisfactory bowel preparation based on OBPS between the two groups when receiving same preparation formula (polyethylene glycol) (OR 0.83; 95%CI: 0.51-1.35; P = 0.46; I² = 39%) as well as receiving same formula and volume (4 L polyethylene glycol) (OR 1.14; 95%CI: 0.65-2.01; P = 0.64; I² = 0%).

CONCLUSION

In patients undergoing afternoon colonoscopies, SaD is comparable with SpD in terms of satisfactory bowel preparation. Further studies are needed to validate these results and determine the optimal formula and dosages.