1. Division of Oncology; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
2. Department of Biostatistics and Epidemiology; University of Pennsylvania; Philadelphia Pennsylvania
3. Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology; University of Pennsylvania; Philadelphia Pennsylvania
4. Department of Anesthesiology and Critical Care Medicine; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
5. Urology Service, Department of Surgery; Memorial Sloan Kettering Cancer Center; New York New York
6. Department of Pediatric Urology; Seattle Children's Hospital; Seattle Washington
7. Department of Animal Biology, School of Veterinary Medicine; University of Pennsylvania; Philadelphia Pennsylvania
8. Department of Urology; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania