1. University of Pennsylvania Perelman School of Medicine, 14640, Division of Pulmonary, Allergy, and Critical Care, Philadelphia, Pennsylvania, United States
2. University of Pennsylvania, 6572, Leonard Davis Institute of Health Economics, Philadelphia, Pennsylvania, United States
3. University of Pennsylvania Perelman School of Medicine, 14640, Palliative and Advanced Illness Research (PAIR) Center, Philadelphia, Pennsylvania, United States;
4. Kaiser Permanente Northern California, 214681, Division of Research, Oakland, California, United States
5. University of Pennsylvania Perelman School of Medicine, 14640, Palliative and Advanced Illness Research (PAIR) Center, Philadelphia, Pennsylvania, United States
6. University of Pennsylvania, 6572, Department of Statistics, The Wharton School, Philadelphia, Pennsylvania, United States
7. University of Pennsylvania Perelman School of Medicine, 14640, Center for Emergency Care Policy and Research, Department of Emergency Medicine, Philadelphia, Pennsylvania, United States