1. Department of Pediatric Emergency Medicine; Changhua Christian Children's Hospital; Changhua Taiwan
2. School of Medicine; Kaohsiung Medical University; Kaohsiung Taiwan
3. Division of Pediatric General Medicine; Department of Pediatrics; Chang Gung Memorial Hospital Taoyuan Taiwan
4. College of Medicine; Chang Gung University; Taoyuan Taiwan
5. Laboratory of Epidemiology and Biostastics; Changhua Christian Hospital; Changhua Taiwan