1. Department of Pediatrics; Texas Children's Cancer Center, Baylor College of Medicine; Houston TX
2. Center for Cancer and Blood Disorders, Children's Medical Center and the Department of Pediatrics, University of Texas Southwestern Medical Center; Dallas TX
3. Division of Pediatric Hematology/Oncology; Seattle Children's Hospital; University of Washington; and Fred Hutchinson Cancer Research Center; Seattle WA
4. Division of Pediatric Epidemiology and Clinical Research; Department of Pediatrics; University of Minnesota; Minneapolis MN
5. Department of Radiation Sciences; Oncology; Umeå University; Umeå Sweden
6. Department of Mathematics and Statistics; University of New Mexico; Albuquerque NM
7. Division of Epidemiology and Biostatistics; Department of Internal Medicine University of New Mexico; Albuquerque NM