School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA. andres.houseman@oregonstate.edu.|Department of Epidemiology, Brown University School of Public Health, Providence, RI, USA. karl_kelsey@brown.edu.|Departments of Neurological Surgery, and Division of Epidemiology, University of California San Francisco, San Francisco, CA, USA. John.Wiencke@ucsf.edu.|Department of Community and Family Medicine, Dartmouth Medical School, Hanover, NH, USA. Carmen.J.Marsit@dartmouth.edu.