Cost–risk–benefit analysis in diagnostic radiology with special reference to the application of referral guidelines

Cost–risk–benefit analysis has been applied to protection of the patient in diagnostic radiology with special reference to the application of referral guidelines. The analysis presented has extended previous work in this field to provide a theoretical framework that encompasses key factors that need to be considered in the optimisation of patient protection from both diagnostic and radiation risks. The fraction of patients whose symptoms do not meet criteria contained in the referral guidelines and, therefore, for whom an X-ray examination is not indicated has been termed the selectivity of the guidelines. Also included are the detriments arising from rejected or repeated examinations as well as the levels of patient dose employed in order to achieve given levels of true and false diagnostic outcomes. A comprehensive framework for optimisation is outlined and its relationship to justification discussed.