Transit through the gut measured by analysis of a single stool.

A method is described for measuring transit time through the gut which requires the collection of only one stool. A dose of 20 radio-opaque markers is given to the subject on each of three consecutive days with breakfast, each dose of marker being of a different type. The first stool passed after rising on the fourth day is collected and its marker content analysed. The method has been validated in 15 subjects by comparing it on 36 occasions with mean transit time measured by a continuous marker technique (MTT-C). In 35 of these studies transit measured from a single stool (SST) and MTT-C were significantly correlated R = 0.78 P less than 0.001. In one study the designated stool contained none of the SST markers. An alternative way of validating the SST method is described by comparing it with the average of the three mean transit times from three separate doses of marker (MTT-S). The average MTT-S agreed very closely with MTT-C in 36 studies R = 0.94 P less than 0.001 and proved a satisfactory alternative method for validating transit techniques. In a total of 66 studies in 22 subjects average MTT-S correlated significantly with SST, R = 0.85 P less than 0.001.