1. Department of Family Medicine, University of Michigan, Ann Arbor, MI, USA
2. Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, USA
3. Department of Emergency Medicine, Harbor-UCLA Medical Center, Los Angeles, CA, USA
4. Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
5. Department of Neurology, University of Michigan, Ann Arbor, MI, USA