摘要:Introduction: The estimated prevalence of functional bowel disorders and its subtypes varies enormously depending on the diagnostic criteria employed. This study aimed at estimating the prevalence and risk factors of functional bowel disorders in an Iranian community. Methods: This study was a cross-sectional household survey conducted from May 2006 to December 2007 in Tehran province, including 18,180 participants who were randomly selected and interviewed face-to-face using a validated questionnaire based on Rome III. Results: In general, 1.1% of the participants met the Rome III criteria for Irritable bowel syndrome (IBS), 1.5% for functional bloating (FB), 2.4% for functional constipation (FC),5.5% for unspecified functional bowel disorder (U-FBD), 0.4% for functional diarrhea (FD) and 10.9% of the participants had at least one type of Functional bowel disorders (FBD). Interestingly, among participants with Functional Dyspepsia, Diarrhea, Bloating, Constipation and Abdominal pain; 83.8%, 78.6%, 77.2%, 74.55%, 72.9% respectively had FBD. Conclusion: This study revealed low rate of Functional Bowel Disorders among urban population of Tehran province. The Rome III criteria itself, and the problems with interpretation of the data collection tool might have taken part in underestimating the prevalence of FBD. In addition the reliability of recall over 6 months in ROME III is questionable for our population.