[1] Western Univ Hlth Sci, Coll Osteopath Med Pacific, Pomona, CA USA
[2] Cedars Sinai Hlth Syst, Smidt Heart Inst, Ctr Cardiac Arrest Prevent, Los Angeles, CA USA
[3] Univ Minnesota, Sch Publ Hlth, Div Epidemiol & Community Hlth, 1300 South 2nd St,Suite 300, Minneapolis, MN 55455 USA