. 2019 Mar 7;20(7):1418–1429. doi: 10.1093/pm/pnz011
© 2019 American Academy of Pain Medicine.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License(http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contactjournals.permissions@oup.com
Figure 1.
Flow diagram of study selection.