[1
]
Department of Family Medicine and Community Health, University of Pennsylvania; Center
for Public Health Initiatives, University of Pennsylvania; Leonard Davis Institute
of Health Economics, University of Pennsylvania. Electronic address: peter.cronholm@uphs.upenn.edu.
[2
]
Department of Epidemiology and Biostatistics, University of Pennsylvania; Violence
Prevention Initiative, Center for Injury Research Prevention.
[3
]
Department of Pediatrics, The Children's Hospital of Philadelphia.
[4
]
Department of Pediatrics, Boston Medical Center, Boston, Massachusetts.
[5
]
Robert Wood Johnson Foundation, Princeton, New Jersey.
[6
]
Philadelphia Health Management Corporation, Drexel University College of Medicine
and St. Christopher's Hospital for Children, Philadelphia, Pennsylvania.
[7
]
Department of Pediatrics, Drexel University College of Medicine and St. Christopher's
Hospital for Children, Philadelphia, Pennsylvania.
[8
]
Violence Prevention Initiative, Center for Injury Research Prevention; Department
of Emergency Medicine, The Children's Hospital of Philadelphia.