1. Department of Epidemiology, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China;
2. Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Los Angeles, USA;
3. School of Medicine, Washington University, St. Louis, Missouri, USA;
4. School of Public Health, University of Texas, Houston, Texas, USA;
5. National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.