1. Department of Public Health, Tzu Chi University, Hualien, Taiwan, ROC
2. Department of Obstetrics and Gynecology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, ROC
3. Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan, ROC
4. Department of Public Health, National Taiwan University College of Public Health, Taipei, Taiwan, ROC
5. Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University College of Public Health, Taipei, Taiwan, ROC
6. Department of Environmental and Occupational Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan, ROC
7. Department of Medical Research, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, ROC