An enquiry into the incidence and prognosis of undiagnosed abdominal pain treated in hospital.

The International Statistical Classification of Diseases, Injuries and Causes of Death contains a special section for 'symptoms and ill-defined condi tions regarding which no diagnosis classifiable elsewhere is recorded'. When a survey was made in the Oxford Record Linkage Study (ORLS) to determine the conditions most commonly leading to hospital inpatient investigation and treatment, it came as a surprise to find that abdominal pain for which no definite explanation could be found (ICD rubric 785-5) was the tenth commonest cause of admission in males and the sixth commonest in females. In this area in 1966 there were 682 dis charges in which unexplained abdominal pain was the final 'diagnosis' reached on the inpatient sum mary. This unexpected finding prompted an investi gation into some of the factors affecting the incidence and prognosis of this condition.