Prospective, randomized, single-blind comparison of two preparations for screening flexible sigmoidoscopy

Gastrointest Endosc. 2000 Aug;52(2):218-22. doi: 10.1067/mge.2000.107907.


Background: The best and most cost-effective bowel cleansing regimen for patients undergoing flexible sigmoidoscopy is not known. The aim of this study was to compare patient tolerance, quality of preparation, and cost of 2 bowel cleansing regimens for flexible sigmoidoscopy.

Methods: Two hundred fifty consecutive patients referred for screening flexible sigmoidoscopy were randomized to receive an oral preparation (45 mL oral sodium phosphate and 10 mg bisacodyl) or an enema preparation (2 Fleet enemas and 10 mg bisacodyl). Tolerance of the preparation was graded as easy, tolerable, slightly difficult, extremely difficult, or intolerable. The endoscopist was blinded to which preparation the patient received and graded the quality of the preparation as poor, fair, good, or excellent. Cost was calculated by adding the cost of the medications and the cost for the nursing time required to prepare the patient for endoscopy.

Results: Patients in the oral preparation group were more likely to grade the preparation as easy or tolerable when compared with the enema group (96.8% vs. 56.4%, p < 0.001). The endoscopist graded the quality of the preparation as good or excellent in 86.5% of the patients in the oral preparation group compared with 57.3% in the enema group (p < 0.001). In the oral preparation group, the mean nursing time (34.6 vs. 65.3 minutes, p < 0.001) and cost ($16.39 vs. $31.13, p < 0.001) were significantly less than in the enema group.

Conclusions: An oral sodium phosphate preparation results in a superior quality endoscopic examination that is better tolerated and more cost-effective than enemas in patients undergoing screening flexible sigmoidoscopy.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Administration, Oral
  • Aged
  • Bisacodyl / administration & dosage*
  • Bisacodyl / economics
  • Cathartics / administration & dosage*
  • Cathartics / economics
  • Chi-Square Distribution
  • Colorectal Neoplasms / diagnosis*
  • Drug Therapy, Combination
  • Female
  • Fiber Optic Technology
  • Humans
  • Male
  • Mass Screening / methods
  • Middle Aged
  • Patient Satisfaction
  • Phosphates / administration & dosage*
  • Phosphates / economics
  • Probability
  • Prospective Studies
  • Sensitivity and Specificity
  • Sigmoidoscopes
  • Sigmoidoscopy / methods*
  • Sigmoidoscopy / nursing


  • Cathartics
  • Phosphates
  • Bisacodyl
  • sodium phosphate