. 2015 Nov 4;2015:160835. doi: 10.1155/2015/160835
Copyright © 2015 Hai-Yong Ren et al.
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.
Flow diagram of the study selection process.