1. Dept. of Radiology, University of Cologne Medical School, Cologne
2. Clinic of the Kapuzinerkarree, Aachen
3. Clinic of Orthopedic and Trauma Surgery, University of Cologne Medical School, Cologne
4. Test Center for Radiation Protection GmbH, Wennigsen
5. Dept. of Medical Statistics, Informatics and Epidemiology, University of Cologne Medical Faculty, Cologne