1. Department of Statistics, Harvard University, Cambridge, Massachusetts, USA
2. Institute of Epidemiology II, Helmholtz Zentrum München German Research Center for Environmental Health, Neuherberg, Germany
3. Department of Environmental Health, and
4. Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
5. VA Boston Healthcare System and the Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA