Self-perceived normality in defecation habits.

Available information on normal bowel habits was mainly gathered by means of telephone interviews or mailed questionnaires.We undertook a prospective study to evaluate the defecatory habits in subjects perceiving themselves as normal concerning this function.A questionnaire (4-week diary with "yes-no" daily answers to six questions concerning bowel habits) was distributed to 204 subjects perceiving their defecation behaviour as normal.The completed questionnaire was returned by 140 subjects. No significant differences were found between sexes or age groups for any variable, even though straining at stool and feeling of incomplete and/or difficult evacuation showed a trend to increase with age. No subject had less than three bowel movements per week or more than three per day. The percentage of symptoms linked to an abnormal defecatory behaviour was well below 10%. Fifty-five percent of subjects reported at least one parameter of abnormal functioning; the most frequent was straining at stool and the rarer was the manual manoeuvres to help defecation.In normal subjects the prevalence of symptoms considered in Rome II criteria as part of an abnormal defecatory behaviour (in more than 25% of defecations) is well below 10%, manual manoeuvres are almost never used to help defecation, and the frequency of defecations is at least three per week.