aEditor-in-Chief, Osong Public Health and Research Perspectives, Korea Centers for Disease Control and Prevention, Cheongju, Korea
bProfessor Emeritus, College of Medicine, Eulji University, Daejeon, Korea
cManaging Editor, Osong Public Health and Research Perspectives, Korea Centers for Disease Control and Prevention, Cheongju, Korea
Copyright ©2017, Korea Centers for Disease Control and Prevention
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
CONFLICTS OF INTEREST
No potential conflict of interest relevant to this article was reported.