1. Department of Pediatrics, Chiang Mai University Medical School, Chiang Mai, Thailand
2. Department of Pediatrics, Louisiana State University Medical School, New Orleans, Louisiana
3. Department of Biometry and Genetics, Louisiana State University School Medical Center, New Orleans, Louisiana
4. Department of Pediatrics, Chiang Mai University Medical School, Chiang Mai, Thailand, Department of Pediatrics, Louisiana State University Medical School, New Orleans, Louisiana