1. University of Michigan Medical School and
2. Department of Public Health, Oxford University, Oxford, United Kingdom;
3. Department of Epidemiology and
4. College of Physicians and Surgeons, Columbia University, New York, New York;
5. Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan;
6. Center for Surgery and Public Health, Harvard School of Public Health; and
7. Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts