Rome III Classification of Functional Gastrointestinal Disorders
| Adult | Infant | Child/adolescent |
| A: Esophageal | G1: Infant regurgitation | H1: Vomiting and aerophagia |
| A1: Heartburn | G2: Infant rumination | H1a: Rumination |
| A2: Chest pain | G3: Cyclic vomiting | H1b: Cyclic vomiting |
| A3: Dysphagia | G4: Infant colic | H1c: Aerophagia |
| A4: Globus | G5: Functional diarrhea | H2: Abdominal pain |
| B: Gastroduodenal | G6: Infant dyschezia | H2a: Dyspepsia |
| B1: Dyspepsia | G7: Functional constipation | H2b: Irritable bowel |
| B2: Belching | H2c: Abdominal migraine | |
| B3: Nausea/vomiting | H2d: Childhood abdominal pain | |
| B4: Rumination | H3: Constipation and incontinence | |
| C: Bowel | H3a: Functional constipation | |
| C1: Irritable bowel | H3b: Nonretentive fecal incontinence | |
| C2: Bloating | ||
| C3: Constipation | ||
| C4: Diarrhea | ||
| C5: Unspecified | ||
| D: Functional abdominal pain | ||
| E: Biliary | ||
| F: Anorectal |