. 2020 Mar 20;99(12):e18969. doi: 10.1097/MD.0000000000018969
Copyright © 2020 the Author(s). Published by Wolters Kluwer Health, Inc.
This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://creativecommons.org/licenses/by/4.0
Figure 3.
Flow diagram of the study selection process.