1. Departments of aEpidemiology
2. Shanghai Institute of Planned Parenthood Research, Shanghai, China
3. General Practice, Institute of Public Health, University of Aarhus, Aarhus, Denmark
4. Department of Neurology and Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark
5. Pediatric Infectious Diseases, Epidemiology and Immunology, Emory University, Atlanta, Georgia
6. Department of Epidemiology, School of Public Health, University of California at Los Angeles, Los Angeles, California