1. Los Angeles County Emergency Medical Services Agency, Los Angeles, California, USA
2. Harbor-UCLA Medical Center, Torrance, California
3. David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California
4. Department of Health Policy and Management, UCLA Fielding School of Public Health, University of California, Los Angeles, California
5. Huntington Medical Research Institutes, Pasadena, California
6. Keck School of Medicine, University of Southern California, Los Angeles, California
7. MemorialCare Heart and Vascular Institute, Long Beach Medical Center, Long Beach, California
8. Department of Neurology, University of California, Los Angeles, California
9. Division of Cardiology, Department of Medicine, University of California, Los Angeles, California