aDepartment of Preventive Medicine and Public Health, Ajou University School of Medicine, Suwon, Korea
bDepartment of Preventive Medicine and Public Health, School of Medicine, Chungnam National University, Gwangju, Korea
cDepartment of Preventive Medicine and Public Health, College of Medicine, Yeungnam University, Daegu, Korea
dDepartment of Preventive Medicine, Chonbuk National University Medical School, Jeonju, Korea
eDepartment of Preventive Medicine, School of Medicine, Gyeongsang National University, Jinju, Korea
fDepartment of Occupational and Environmental Medicine, Ajou University School of Medicine, Suwon, Korea
gGraduate School of Public Health, Ajou University, Suwon, Korea
© 2014 Published by Elsevier B.V. on behalf of Korea Centers for Disease Control and Prevention.
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