1. Department of Biostatistics and Epidemiology, Amherst School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA, USA
2. Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
3. Department of Health Promotion and Policy, Amherst School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA, USA