Progress in diagnostic imaging raises the question of whether conventional skull radiology is still legitimate even though, with computer tomography (CT), a technique is available that can clearly and safely diagnose intracranial haemorrhage and other sequelae of cerebral trauma. The intention of our investigation was therefore to weigh up the advantages and disadvantages of conventional skull radiology compared with cerebral computer tomography as the primary radiological diagnostic tool in mild traumatic brain injury. In the period of 1st January to 31st December the Interdisciplinary Emergency Department of the University Hospital Basel treated 378 patients with a diagnosis of mild closed traumatic brain injury. By means of a special exclusion criterion, 85 of those patients could be included, prospectively randomised in the Quality Control Commotio Cerebri 2001, 43 patients were in the Rx-group and 42 in the CT-group. The patients of the CT-group underwent a cerebral computed tomographic scan 1 to 4 hours after the casualty. All patients were checked 4 to 6 weeks later using a standardised questionnaire. In the CT-group, 3 patients showed an osseous fracture, but no intracranial haemorrhage. However, the retrospective evaluation of 119 patients originally excluded revealed 7 cases of intracranial haemorrhage. The advantage of primary CT versus the conventional imaging techniques is the fast discovery of possible intracranial trauma sequelae, with or without osseous skull fracture. The average duration of stay was 20 to 24 hours in the Rx-group and 14½ hours in the CT-group. The average total cost of treatment was comparable, CHF 1387 (Rx-group) versus CHF 1470 (CT-group). The treatment scheme of the CT-group is the more reasonable one, since in this group the shorter hospitalisation period requires fewer personnel and resource expenditure. The most common symptoms in the reviews were headaches (60%), difficulties in concentrating (38%), dizziness (35%), this in terms of post-commotional syndrome. Following the results of our investigations, we recommend CT for the primary evaluation of mild traumatic brain injury provided the infrastructure of the hospital can guarantee an organised 24-hour CT-service. Compared with conventional skull radiology, CT enhances patient security, shortens the clinical observation period and contributes to a better cost benefit.