1. 1Department of Biostatistics, School of Public Health and The Key Laboratory of Public Health Safety of Ministry of Education, Fudan University, Shanghai, China
2. 2Department of Clinical Medicine-Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark
3. 3Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA
4. 4Department of Statistics, College of Letters and Science, University of California, Los Angeles (UCLA), Los Angeles, CA
5. 5Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark