1 Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California.
2 Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Centre for Public Health Sciences, University of Iceland, Reykjavik, Iceland.
3 Epidemiology, Biostatistics and Biodemography, Department of Public Health, Odense, Denmark; The Danish Twin Registry, University of Southern Denmark, Odense, Denmark.