Definition and classification of irritable bowel syndrome: Current consensus and controversies

Both consensus and controversy exist regarding the taxonomy of irritable bowel syndrome. Recent research has increased controversy about its definition and classification, even whether it is functional or organic, and there are other important semantic issues. Consensus on the diagnostic symptom criteria is an evolving process, and varied estimated prevalence rates may be caused by varied criteria used and other methodological factors. The Manning and Rome II criteria are used inconsistently in practice, especially in primary care, but they have been important in research on epidemiology and therapy. Although primary care patients predominate in practice, most research has been conducted on referral patients, and recruitment methods and other factors influence the generalizability of the results.