Supplementary materials: Handling related publications reporting real-world evidence in network meta-analysis: a case study in multiple sclerosis

These are peer-reviewed supplementary materials for the article 'Handling related publications reporting real-world evidence in network meta-analysis: a case study in multiple sclerosis' published in the Journal of Comparative Effectiveness Research.Supplementary Table 1: PubMed Search AlgorithmSupplementary Table 2: Embase Search AlgorithmSupplementary Table 3: SLR Eligibility CriteriaSupplementary Figure 1: PRISMA Diagram – SLR AttritionThree-level Meta-analysis Using Hypothetical Data from Related Study Publications of Real-world Evidence DatabasesSupplementary Table 4: Exemplar Scenarios with hypothetical data from 10 studiesData AnalysisAim: The presence of two or more publications that report on overlapping patient cohorts poses a challenge for quantitatively synthesizing real-world evidence (RWE) studies. Thus, we evaluated eight approaches for handling such related publications in network meta-analyses (NMA) of RWE studies. Methods: Bayesian NMAs were conducted to estimate the annualized relapse rate (ARR) of disease modifying therapies in multiple sclerosis. The NMA explored the impact of hierarchically selecting one pivotal study from related publications versus including all of them while adjusting for correlations. Results: When selecting one pivotal study from related publications, the ARR ratios were mostly similar regardless of the pivotal study selected. When including all related publications, there were shifts in the point estimates and the statistical significance. Conclusion: An a priori hierarchy should guide the selection among related publications in NMAs of RWE. Sensitivity analyses modifying the hierarchy should be considered for networks with few or small studies.