1. Department of Surgery, University Hospital Regensburg, 93053 Regensburg, Germany
2. Department of Pediatric Surgery and Pediatric Orthopedics, Hospital St. Hedwig of the Order of St. John of God, University Children’s Hospital Regensburg (KUNO), Steinmetzstrasse 1-3, 93049 Regensburg, Germany
3. Department of Statistical Bioinformatics, University of Regensburg, 93053 Regensburg, Germany
4. Department of Hand, Plastic and Reconstructive Surgery, BG Unfallklinik Tuebingen, Eberhard Karls University, 72074 Tuebingen, Germany
5. Department of Pediatric Urology, Hospital St. Hedwig of the Order of St. John of God, University Children’s Hospital Regensburg (KUNO), Steinmetzstrasse 1-3, 93049 Regensburg, Germany
6. Pediatric Surgery, RoMed Klinikum Rosenheim, 83022 Rosenheim, Germany