1. Metabolic Epidemiology Branch, Division of Cancer Epidemiology & Genetics National Cancer Institute Bethesda Maryland USA
2. Epidemiology Branch National Institute of Environmental Health Sciences Research Triangle Park North Carolina USA
3. Biostatistics Branch, Division of Cancer Epidemiology & Genetics National Cancer Institute Bethesda Maryland USA
4. Biostatistics and Computational Biology Branch National Institute of Environmental Health Sciences Research Triangle Park North Carolina USA