Bayesian network meta-analysis of multiple outcomes in dental research

Abstract Objectives Dental research typically targets multiple outcomes. Interdental cleaning devices such as interdental brushes (IB), and waterjet devices (WJ) share a sizable portion of the medical device market. However, recommendations for device selection are limited by the conflicting evidence from multiple outcomes in available studies and the lack of an appropriate synthesis approach to summarize evidences taken from multiple outcomes. In particular, both pairwise meta-analyses and single-outcome network meta-analyses can give discordant results 1 , 2 , 3 , 4 , 5 . The purpose of this multi-outcome, Bayesian network meta-analysis is to introduce this innovative method to the dental research community using data from interdental cleaning device studies for illustrative purposes. Methods We reanalyzed a network meta-analysis of interproximal oral hygiene (IOH) methods in the reduction of clinical indices of inflammation, which included 22 trials assessing 10 IOH aids. We focused on the primary outcome of gingival inflammation, which was measured by two correlated outcome variables, the Gingival Index (GI) and Bleeding on probing (BOP). Results In our previous single-outcome analysis, we concluded that IB and WJ rank high for reducing gingival inflammation while TP and FL rank last. In this multi-outcome Bayesian network meta-analysis with equal weight on GI and BOP the surface under the cumulative ranking curve (SUCRA) was 0.87 for WJ and 0.85 for IB. WJ and IB remained ranked as the two best devices across different sets of weightings for the GI and BOP. Conclusion In conclusion, multi-outcome Bayesian network meta-analysis naturally takes the correlations among multiple outcomes into account, which in turn can provide more comprehensive evidence.