From the Departments of Surgery (A.L.D., B.H.M., E.A.R., E.D., D.H.F., S.E.R., M.A.S., M.F.) and Emergency Medicine (J. Jui), Oregon Health and Science University, Portland, Oregon; Departments of Emergency Medicine (J.M.) and Surgery (J. Johannigman), University of Cincinnati, Cincinnati, Ohio; Departments of Surgery (B.R.H.R., E.M.B., P.K.) and Biostatistics (D.K., B.M., E.N.M., S.M., K.S., J.H.), University of Washington, Seattle, Washington; Trauma Surgery (B.T.), Texas Health Presbyterian Hospital; Department of Emergency Medicine (J.S.G.), Baylor University Medical Center, Dallas, Texas; Johns Hopkins School of Medicine (M.L.W.), Baltimore, Maryland; Department of Emergency Medicine (T.P.A., M.R.C.), Medical College of Wisconsin, Milwaukee, Wisconsin; Department of Emergency Medicine (J.M.T., J.C.), University of British Columbia, Vancouver, British Columbia, Canada; Department of Surgery (S.E.R.), Scripps Memorial Hospital La Jolla, La Jolla, California; Departments of Emergency Medicine (A.H.I.) and Internal Medicine (A.H.I.), University of Texas Southwestern Medical Center, Dallas, Texas; Providence Health Care Research Institute (J.C.), Vancouver, British Columbia, Canada; Rescu, Li Ka Shing Knowledge Institute (L.J.M.), and Department of Surgery (S.R.), St. Michael's Hospital; Division of Emergency Medicine, Department of Medicine Faculty of Medicine (L.J.M.), and Department of Laboratory Medicine and Pathobiology (J.C.), University of Toronto, Toronto, Ontario, Canada; Departments of Emergency Medicine (R.J.F.) and Surgery (D.J.D.), Regions Hospital, St. Paul, Minnesota; Department of Surgery (C.W., P.L.B.), University of Alabama, Birmingham, Alabama; Department of Surgery (C.E.W., B.A.C., L.E.V.), McGovern Medical School, University of Texas Health Science Center, Houston, Texas; Department of Laboratory Medicine and Molecular Diagnostics (J.C.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada; Departments of Emergency Medicine (N.J.R.) and Surgery (R.R.G.), John Peter Smith Health Network, Fort Worth, Texas; Department of Surgery (M.D.Z., M.F.), Mayo Clinic, Rochester, Minnesota; British Columbia Emergency Health Services (J.M.T., R.S.), Vancouver, British Columbia, Canada; Department of Emergency Medicine (L.K., A.H.), Hennepin County Medical Center, Minneapolis, Minnesota; Department of Surgery (S.R.), St. Michael's Hospital, Toronto, Ontario, Canada; Department of Emergency Medicine (M.G.), Medical City Plano, Plano; Emergency Medicine (R.S.), Methodist Dallas Medical Center, Dallas, Texas; National Heart, Lung, and Blood Institute, National Institutes of Health (G.S.), Bethesda, Maryland; and Department of Trauma Surgery (W.W.), Texas Health Harris Methodist Hospital, Fort Worth, Texas.