1. Department of Emergency Medicine (M.E.W., M.L.M.), The George Washington University, Medical Faculty Associates, Washington, DC.
2. Department of Health Policy and Management (Z.Z., Y.L., M.L.M.), The George Washington University, Washington, DC.
3. Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.L.Z.).
4. Department of Epidemiology and Biostatistics (A.E.), Milken Institute School of Public Health, The George Washington University, Washington, DC.
5. Division of Cardiology (R.J.K.), The George Washington University, Medical Faculty Associates, Washington, DC.