1. Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN, USA
2. College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
3. Department of Epidemiology, Shanghai Cancer Institute, Shanghai, China
4. Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA