The Rome III criteria system was developed to classify the functional gastrointestinal disorders based on clinical symptoms. Each disorder has its own set of criteria. For example, the Rome III criteria for irritable bowel syndrome (IBS) is as follows:
Symptoms of recurrent abdominal pain or discomfort and a marked change in bowel habit for at least six months, with symptoms experienced on at least three days of at least three months. Two or more of the following must apply:
- Pain is relieved by a bowel movement
- Onset of pain is related to a change in frequency of stool
- Onset of pain is related to a change in the appearance of stool.
Source: Functional Bowel Disorders (2006). Longstreth, G.F., et.al. Gastroenterologyy 130:1480-1491.