Cystourethrography procedures in children. Evaluation of benefits versus dose.

Cystourethrography was used by the referring physician in 53 children with urinary tract disease. The benefits of this technique were evaluated using Bayesian methods. Prior and subsequent odds of the accuracy of the clinical diagnosis being affected by the radiological procedure were estimated. Marked benefits were found in 12 cases, which were used as the basis for the most conservative estimate of benefits. The genetic benefit-risk ratio is 140 for boys and 8.3 for girls. The somatic benefit-risk ratio is 10,000 for boys and 4,200 for girls.