Lurie Children's Hospital of Chicago, Lurie Children's Hospital of Chicago, Harvard University - Dana-Farber Cancer Institute, The Hospital for Sick Children - Division of Hematology/Oncology, University of Alabama at Birmingham - Institute for Cancer Outcomes and Survivorship, Children’s Hospital of Philadelphia, St. Jude Children’s Research Hospital, University of Calgary, St. Jude Children’s Research Hospital, City of Hope - Department of Population Sciences, The Children's Oncology Group (COG) Statistics and Data Center (SDC) - Department of Biostatistics, Harvard University - Dana-Farber Cancer Institute, University of Southern California - Children’s Hospital Los Angeles, University of Pennsylvania - Division of Oncology, Harvard University - Dana-Farber Cancer Institute and Harvard University - Dana-Farber Cancer Institute