Utilization and cost-effectiveness of cranial computed tomography at a university hospital.

This study prospectively surveyed the utilization of cranial computed tomography (CCT) at The George Washington University Hospital over a 12-month period. Of 3,070 CCT scans studied, 1,098 (35%) resulted in a positive clinically important diagnosis for an overall case finding cost of $800. Within each of 25 individual indications for scanning, classified on the basis of the patient's most specific sign or symptom, case finding costs varied from a low of $411 for patients in coma to $3,500 for patients with headaches as their only indication for CT scanning. Within two diagnostic categories, malignant brain tumors and cerebral aneurysms, there was significant agreement (p less than 0.001) between the prescanning diagnosis and the result on CCT. Overall there was also close agreement (correlation coefficient = 0.706) between the rank listing of the 25 indications for scanning compiled prior to CCT with that obtained after the scanning results were known.