Netowrk meta-analysis is advanced method of meta-analysis that can incorporate several interventions and compare them (directliy and inderectly) simultaneously (Dias et al. 2013).
In a summary, data from randomized controlled trials can be combined (A vs. B, A vs. C, B vs. D, etc.) to deliver an internally consistent set of estimates while respecting the randomization in the evidence.
In this initial tutorial I present the code necessary to conduct a Network meta-analysis in R with available dataset. For further information a recommend the book Doing Meta-Analysis with R: A Hands-on Guide by Mathias Harrer et al.