. 2019 May 16;2019:7305750. doi: 10.1155/2019/7305750
Copyright © 2019 Dingjian Wang and Guixia Pan.
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.
A flowchart of the included and excluded studies.