1. Department of Population Health Sciences (S.D.R., F.R.J., J.M.G.), Duke University School of Medicine, Durham, NC.
2. Duke Clinical Research Institute (S.D.R., A.O.F., F.R.J., J.M.G., R.J.M., M.W.K., S.V.), Duke University School of Medicine, Durham, NC.
3. Division of Cardiology, Department of Medicine (R.J.M., M.W.K., S.V.), Duke University School of Medicine, Durham, NC.