. 2010 Dec 7;1(1):55–60. doi: 10.1016/j.phrp.2010.12.012
© 2010 Published by Elsevier B.V. on behalf of Korea Centers for Disease Control and Prevention.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
Study population flow chart.