aDepartment of Preventive Medicine, College of Medicine, Konyang University, Daejeon, Korea.
bDepartment of Preventive Medicine, College of Medicine, Eulji University, Daejeon, Korea.
cDepartment of Hospital Administration, Konyang Cyber University, Daejeon, Korea.
dDivision of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA.
eDivision of Vaccine Preventable Disease Control and National Immunization Program, Korea Centers for Disease Control and Prevention, Osong, Korea.
Copyright ©2013, Korea Centers for Disease Control and Prevention
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