1. Department of Urology University Hospital Leipzig Leipzig Germany
2. Clinical Trial Center Leipzig Leipzig University Leipzig Germany
3. Institute for Medical Informatics, Statistics and Epidemiology Leipzig University Leipzig Germany
4. Department of Urology Klinikum Dortmund Dortmund Germany
5. Department of Urology Sana Hospital Borna Borna Germany
6. Department of Urology University Hospital Heidelberg Heidelberg Germany
7. Department of Urology Staedtisches Klinikum Karlsruhe Karlsruhe Germany
8. Department of Urology University Hospital Duesseldorf Duesseldorf Germany
9. Department of Urology Marien Hospital Duesseldorf Duesseldorf Germany