There is no current consensus as to an organic cause of this syndrome and there generally appears to be no sign of disease upon physical examination except for tenderness over the large intestine. The diagnosis is symptom-based, usually through identification of the ROME II criteria for IBS. These criteria which have been accepted worldwide by clinicians and researchers as the standard for IBS diagnosis are as follows: At least 12 weeks, which need not be consecutive, in the preceding 12 months of abdominal discomfort or pain that has two of three features: