. 2017 Dec 20;2017:2504021. doi: 10.1155/2017/2504021
Copyright © 2017 Yi-Hua Liu 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 studies included in the review.