This is an emipirically derived questionnaire to measure non-gastrointestinal symptoms that co-exist with Irritable Bowel Syndrome (IBS). Factor analysis of IBS patient symptoms were used to develop the scale and the instrument is rated with 4 subscales: one for psychiatric disorders and 3 for different types of somatic disorders. Concurrent validity was shown with strong correlations with the Cornell Medical Index and the Brief Symptom Inventory – 18.