1 Veterans Affairs Ann Arbor, Ann Arbor, Michigan; National Clinician Scholars Program, University of Michigan, Ann Arbor, Michigan; Department of Surgery, Yale School of Medicine, New Haven, Connecticut.
2 Veterans Affairs Ann Arbor, Ann Arbor, Michigan; Center for Healthcare Outcomes and Policy, University of Michigan, Ann Arbor, Michigan.
3 Center for Healthcare Outcomes and Policy, University of Michigan, Ann Arbor, Michigan; Department of Surgery, University of Michigan, Ann Arbor, Michigan.