1 Department of Pediatrics, Kuang-Tien General Hospital, Taichung, Taiwan; Department of Nutrition, Hungkuang University, Taichung, Taiwan.
2 Department of Pediatrics, China Medical University Children Hospital, Taichung, Taiwan; Department of Public Health, China Medical University, Taichung, Taiwan.
3 Department of Pediatrics, Department of Medical Research, Tungs' Taichung Metroharbor Hospital, Taichung, Taiwan.
4 Department of Pediatrics, Kuang-Tien General Hospital, Taichung, Taiwan.
5 Research and Diagnosis Center, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan. Electronic address: jyyang@cdc.gov.tw.