1. Institute of Statistics Ulm University Ulm Germany
2. Clinical Trials Unit Faculty of Medicine and Medical Center—University of Freiburg Freiburg Germany
3. Hematology, Oncology, and Stem‐Cell Transplantation Faculty of Medicine and Medical Center—University of Freiburg Freiburg Germany
4. Institut für Medizinische Statistik Universitätsmedizin Göttingen Göttingen Germany