NMA: Network meta-analysis based on multivariate meta-analysis and meta-regression models in R

Abstract Network meta-analysis has become an established methodology within systematic reviews for comparing the effectiveness of multiple treatments and is now a standard approach in comparative effectiveness research. However, the underlying statistical methods are often highly technical for non-statisticians in practice. To complement existing software, we developed NMA , a comprehensive R package organized around the multivariate meta-analysis and meta-regression framework and designed to provide a broad range of analytical and graphical tools through simple commands. The NMA package provides tools for evidence synthesis, network meta-regression, assessment of heterogeneity and inconsistency, comparative effectiveness analyses, and graphical visualization. It also incorporates higher-order inferential and prediction procedures and data-handling functions that facilitate the integration of arm-level data and summary effect estimates. In this article, we provide a gentle introduction to the NMA package and illustrate its application through a case study of a network meta-analysis of antihypertensive drugs.