1. (Cases 1, 2, 3) Doernbecher Children's Hospital, Oregon Health & Science University, Portland, Ore
2. (Cases 1, 2, 3) Associate Editor, Pediatrics in Review
3. (Case 4) Departments of Pediatrics, Epidemiology and Biostatistics, Division of General Pediatrics, Institute for Health Policy Studies, UCSF Children's Hospital, University of California, San Francisco, Calif
4. (Case 4) Department of Pediatrics, Division of General Pediatrics, Institute for Health Policy Studies, UCSF Children's Hospital, University of California, San Francisco, Calif