An office guide to whole-gut transit time. Patients' recollection of their stool form.

Forty-seven patients (ages 17-74 years, 33 women) who had irritable bowel syndrome and who attended a gastroenterology clinic had their whole-gut transit time (WGTT) assessed by an abdominal radiograph after ingesting 20 radioopaque markers on 4 consecutive days. Immediately afterward, the patients completed a questionnaire that asked about their stool form on the Bristol Scale, their bowel frequency, and whether they thought they had been experiencing diarrhea or constipation during the previous 5 days. WGTT varied from 7 to 96 h. Stool form correlated significantly with WGTT (r = -0.57, p < 0.001), whereas stool frequency did not (r = 0.31, NS). The regression equation relating WGTT to stool form was WGTT (h) = 75-10 (stool form). WGTT, stool form, and frequency were significantly different in patients reporting constipation compared with those who reported diarrhea, diarrhea and constipation, or neither, but in the last three groups these parameters were not significantly different from each other. Patients' recollection of stool form is a reasonable guide to their transit time and can be used in the office to identify pseudodiarrhea and true constipation.