1 Institute for Firearm Injury Prevention, University of Michigan, Ann Arbor, Michigan (M.D.E.).
2 Institute for Firearm Injury Prevention and School of Social Work, University of Michigan, Ann Arbor, Michigan (R.L.S.).
3 Institute for Firearm Injury Prevention, University of Michigan, and Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, Michigan (D.J.W.).