The Impact of a Preauthorization Policy on the After-hours Utilization of Emergency Department Computed Tomography Imaging

This study demonstrates a trend toward increased utilization of CT resources after implementation of an ED preauthorization policy with most study types showing significantly increased utilization. In the case of neurological examinations, a potential “substitution effect” was observed, whereby the rates of neuroangiographic studies showed a marked increase, offsetting the decrease in general neurological examinations performed. Departments considering implementation of preauthorization policies should weigh carefully the benefits of ED workflow efficiencies against the potential harms of increased CT use.