1. Center for Cancer Research and
2. Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD;
3. Division of Hematology and Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN;
4. Division of Epidemiology and Vanderbilt Epidemiology Center, Department of Medicine, Vanderbilt University School of Medicine, and the Vanderbilt-Ingram Cancer Center, Nashville, TN; and
5. International Epidemiology Institute, Rockville, MD