. 2014 Jul 13;2014:430195. doi: 10.1155/2014/430195
Copyright © 2014 S. K. Tang and M. Y. M. Tse.
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
Conceptual framework of the present study.