1. San Francisco Department of Public Health, San Francisco, CA, USA
2. Divisions of Biostatistics and Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, CA, USA
3. Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
4. Department of Emergency Medicine, University of California, San Francisco, San Francisco, CA, USA
5. Department of Anesthesia, University of California, San Francisco, San Francisco, CA, USA