Epidemiological study on patient exposure to medical radiation

Several aspects of radiation risk were studied: 1) epidemiology, 2) X-ray mass surveys, 3) factors related to patients dose, 4) clinical judgment and the indications for X-ray examination, 5) abdominal X-rays of women of child bearing age, 6) irradiation of the fetus, and 7) radiotherapy for benign disease. The survey results showed that 1) frequent fluoroscopic examinations may be related to late induction of leukemia, 2) radiation risk in X-ray mass surveys can be reduced by solving some technical problems and general problems of mass screening, 3) patients with high benefit health insurance tend to receive more X-rays than patients with low benefit insurance, 4) of 2000 patients on whom gastrointestinal tract X-ray examinations were requested, no necessity for the examination was recognized in 10% of the cases, 5) only about half of the female patients of child bearing age were checked for menstrual cycle at the time of an X-ray study, 6) radiodiagnostic histories of 1485 pregnant women showed that 22% were X-rayed at any time during the gestation period, with an over age dose of 61 mrad (a dose which would correspond to introduction of 19.5 excess leukemias in children under the age of 10 years), and 7) about 10% of the patients in radiotherapy departments are being treated for benign diseases. (Evans, J.)