Figures & data
Figure 1. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram [16].
![Figure 1. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram [16].](/cms/asset/cbb48a76-a8d8-4346-b67c-7fad2a499f2c/icop_a_1815183_f0001_c.jpg)
Table 1. Definition of exacerbation in the included studies:.
Table 2. NIH quality assessment tool of included non-randomized studies.
Table 3. Risk of bias assessment of the included RCT.