^aFrom the aInstitute for Health Metrics and Evaluation, Seattle, WA

^bNational Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, RTP, NC

^cDepartment of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA

^dSchool of Population and Public Health, The University of British Columbia, Vancouver, BC, Canada.

Supported in part by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Environmental Health Sciences. K.C. is supported by the Bill & Melinda Gates Foundation.

Disclosure: The authors report no conflicts of interest.

Correspondence: Stephanie J. London, NIEHS, PO Box 12233, MD A3-05, RTP NC 27709. E-mail [email protected].