1. Department of Research and Evaluation Kaiser Permanente Southern California Pasadena CA
2. Department of Emergency Medicine Los Angeles Medical Center Kaiser Permanente Southern California Los Angeles CA
3. Department of Emergency Medicine San Diego Medical Center Kaiser Permanente Southern California San Diego CA
4. Department of Emergency Medicine Harbor‐UCLA Medical Center Torrance CA
5. Department of Emergency Medicine Kaiser Permanente Sacramento Medical Center Sacramento CA
6. The Permanente Medical Group and Kaiser Permanente Division of Research Oakland CA
7. Department of Emergency Medicine University of California Los Angeles CA