title: Statistical analysis of the lactulose/breath hydrogen test in the measurement of orocaecal transit: its variability and predictive value in assessing drug action.
abstract: The variability in the orocaecal transit time as measured by the lactulose/breath hydrogen method has been studied for three conditions: lactulose given with a meal, subjects sitting; lactulose given with a meal, subjects semirecumbent; lactulose given in aqueous solution, subjects semirecumbent. Thirty three healthy subjects attended on up to 12 occasions. It was found that administration of the lactulose with a meal significantly reduced the variability (p less than 0.05) and that adoption of the semirecumbent position further reduced variability. A power analysis was used to predict the number of subjects who would be required to show a given percentage change in orocaecal transit time at specified probabilities and powers. A graph and a table for use in the prediction of subject numbers at a probability of 5% and for powers of 50-99% is presented. A dose response curve for metoclopramide using the lactulose/breath hydrogen method is given for doses of 10, 15, and 20 mg.
authors.affiliation: Clinical Pharmacology Unit, West Middlesex University Hospital, Isleworth.
authors.forename: D H
authors.initials: DH
authors.lastname: Staniforth
authors.forename: D
authors.initials: D
authors.lastname: Rose
mesh_terms: D001944:Breath Tests; D004187:Disaccharides; D004305:Dose-Response Relationship, Drug; D005772:Gastrointestinal Transit / Q000187:drug effects; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007792:Lactulose / Q000378:metabolism; D008722:Methods; D008787:Metoclopramide / Q000494:pharmacology; D011237:Predictive Value of Tests
chemical_list: D004187:Disaccharides; D007792:Lactulose; D006859:Hydrogen; D008787:Metoclopramide