1 Harborview Injury Prevention and Research Center, Harborview Medical Center, University of Washington, 401 Broadway Suite 2075, Seattle, WA, 98104, USA. lprater@uw.edu.
2 Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA. lprater@uw.edu.
3 Harborview Injury Prevention and Research Center, Harborview Medical Center, University of Washington, 401 Broadway Suite 2075, Seattle, WA, 98104, USA.
4 Department of Pediatrics, University of Washington, Seattle, WA, USA.
5 Department of Medicine, University of Washington, Seattle, WA, USA.
6 Department of Health Services, School of Public Health, University of Washington, Seattle, WA, USA.