1. Masonic Cancer Center; University of Minnesota; Minneapolis MN
2. University of Pittsburgh Cancer Institute; Pittsburgh PA
3. Department of Epidemiology, Graduate School of Public Health; University of Pittsburgh; Pittsburgh PA
4. Centers for Disease Control and Prevention; Atlanta GA
5. Department of Epidemiology; Shanghai Cancer Institute, Shanghai Jiaotong University; Shanghai China
6. Division of Environmental Health Sciences; University of Minnesota; Minneapolis MN