. 2010 Oct 15;10:558. doi: 10.1186/1471-2407-10-558
Copyright ©2010 Zhang et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
A flow chart showing the selection of the trials.