. 2016 Nov 6;2016:3915237. doi: 10.1155/2016/3915237
Copyright © 2016 Hao Jiang 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 6.
Funnel plot of NPPV on total mortality.