1. Center for Injury Research and Policy, The Research Institute at Nationwide Children's Hospital, Columbus, OH
2. The Ohio State University, School of Physical Activity and Educational Services, Columbus
3. The Ohio State University, College of Medicine, Department of Pediatrics and College of Public Health, Division of Epidemiology, Columbus. Dr Fields is now at the Department of Communication, University of Colorado, Denver. Dr Comstock is now at the School of Medicine, Pediatric Injury Prevention, Education, and Research (PIPER) program, and Colorado School of Public Health, Department of Epidemi