1. Faculty of Statistics, TU Dortmund University, Dortmund, Germany
2. Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund (IfADo), Dortmund, Germany
3. Department of Urology, Knappschaftskrankenhaus, Dortmund, Germany
4. Department of Urology, St-Josefs-Hospital, Dortmund, Germany
5. Department of Urology, Klinikum Dortmund gGmbH, Dortmund, Germany