University of North Carolina, Gillings School of Global Public Health, Chapel Hill, North Carolina. hazel.nichols@unc.edu. Division of Genetics and Epidemiology, The Institute of Cancer Research, Sutton, United Kingdom. University of North Carolina, Gillings School of Global Public Health, Chapel Hill, North Carolina. Karolinska Institutet, MEB, University of Oslo Institute of Health and Society, Sweden, Norway. Fondazione IRCCS Istituto Nazionale dei Tumori, Italy, France. Centre for Research in Epidemiology and Population Health (CESP), France. Beckman Research Institute of City of Hope, Monrovia, California. Slone Epidemiology Center at Boston University, Boston, Massachusetts. Division of Epidemiology, Department of Medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee. University of Pittsburgh Graduate School of Public Health, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania. NYU School of Medicine, New York, New York. Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, Maryland. International Agency for Research on Cancer, France. Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard T.H. Chan School of Public Health and Harvard Medical School, Boston, Massachusetts. Cancer Council Victoria, University of Melbourne, Melbourne, Australia. University of Tromsø, The Arctic University of Norway, Tromsø, Norway. Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts, Boston, Massachusetts. Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland. Division of Cancer Epidemiology, DKFZ, Heidelberg, Germany. University of Oxford, Oxford, United Kingdom. Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada. Duke-NUS Medical School, Singapore. Karolinska Institutet, Institute of Environmental Medicine, Stockholm, Sweden. UiT (University of Tromsø), Tromsø, Norway. School of Public Health, Imperial College London, United Kingdom. Department of Epidemiology, Murcia Regional Health Council, IMIB-Arrixaca, Murcia, Spain. CIBER Epidemiología y Salud Pública (CIBERESP); Department of Health and Social Sciences, Universidad de Murcia, Murcia, Spain. Department of Public Health, Section for Epidemiology, Aarhus University, Aarhus, Denmark. Radiation Effects Research Foundation, Hiroshima, Japan. University Medical Center, Utrecht, the Netherlands. Albert Einstein College of Medicine, Bronx, New York. Umeå University, Umeå, Sweden. Hellenic Health Foundation, Greece. Norwegian University of Science and Technology, Trondheim, Norway. Johns Hopkins School of Medicine, Baltimore, Maryland. Karolinska Institutet, Department of Epidemiology and Biostatistics, Oslo, Norway. Department of Research, Head, Group of Etiological Cancer Research, Cancer Registry of Norway, Institute of Population-Based Cancer Research, Oslo, Norway. Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland. Department of Community Medicine, University of Tromsø, The Arctic University of Norway, Tromsø, Norway. Department of Nutrition and Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts. Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, North Carolina. Division of Breast Cancer Research, The Institute of Cancer Research, London, United Kingdom.