1. Academic Rheumatology (A.S., J.H.T.), Clinical Science at North Bristol, University of Bristol, Bristol BS10 5NB, United Kingdom;
2. Department of Epidemiology (M.M.), Rollins School of Public Health, Emory University, Atlanta, Georgia 30322;
3. National Center for Environmental Health (M.M., C.R., M.A.M.), Centers for Disease Control and Prevention, Atlanta, Georgia 30333