Network meta-analysis: an introduction for clinicians

Abstract

Network meta-analysis is a technique for comparing multiple treatments simultaneously in a single analysis by combining direct and indirect evidence within a network of randomized controlled trials. Network meta-analysis may assist assessing the comparative effectiveness of different treatments regularly used in clinical practice, and therefore has become attractive among clinicians. However, if proper caution is not taken in conducting and interpreting network meta-analysis, inferences might be biased. The aim of this paper is to illustrate the process of network meta-analysis with the aid of a working example on first-line medical treatment for primary open-angle glaucoma. We discuss the key assumption of network meta-analysis, as well as the unique considerations for developing appropriate research questions, conducting the literature search, abstracting data, performing qualitative and quantitative synthesis, presenting results, drawing conclusions, and reporting the findings in a network meta-analysis.

Comparative Efficacy of Targeted Therapies in Patients with Non-Small Cell Lung Cancer: A Network Meta-Analysis of Clinical Trials

“…We measured inconsistency, which implies statistical disagreement between direct and indirect comparisons [12,13]. The generalized linear model was applied for the Bayesian NMA [14].…”

Network meta-analysis: a technique to gather evidence from direct and indirect comparisons

“…Traditional meta-analytical methods refer to pairwise comparisons between an intervention and a control, typically a placebo or other active intervention 13,14. This standardized approach allows examining the existing literature on a specific issue to determine whether a conclusion can be reached regarding the effect of a treatment.…”

Indirect treatment comparisons and biologics

“…A network meta-analysis (NMA) builds evidence by combining results from head-to-head trials (direct evidence) with results from common comparator trials (indirect evidence), whereas a traditional meta-analysis includes only head-to-head trials. 6 Although some degree of variation across study populations is acceptable in a traditional meta-analysis, it can be disastrous in an NMA. Because an NMA combines 2 different types of trials, it necessitates the assumption of ''consistency,'' which means that the indirect and direct evidence is congruent; that is, if the indirect evidence from the common comparator trials included in the NMA indicates that treatment X is superior to treatment Y, then such differences also should be seen in head-to-head trials.…”