1. Department of Medicine, Division of Cardiology (M.F., W.S.J., A.F.H., M.R.P.)
2. Duke Clinical Research Institute, and Department of Anesthesiology, Division of Pain Medicine (R.L.B.-M., A.G.), Duke University School of Medicine, Durham, NC.
3. Department of Biostatistics and Bioinformatics (C.L.G.)