. 2019 Mar 22;98(12):e14852. doi: 10.1097/MD.0000000000014852
Copyright © 2019 the Author(s). Published by Wolters Kluwer Health, Inc.
This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial License 4.0 (CCBY-NC), where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc/4.0
Figure 3.
Funnel plot (Publication bias).