Bibliographic study showed improving statistical methodology of network meta-analyses published between 1999 and 2015

Abstract

Objective: To assess the characteristics and core statistical methodology specific to network meta-analyses (NMAs) in clinical research articles. Study Design and What is new?Key findings Although the amount of evidence (the number of treatments and studies) included in published NMAs remains stable, the undertaking and reporting of statistical methods have significantly improved over the years. The assumptions underlying NMA are increasingly discussed and evaluated using appropriate methods. Less than 10% of NMAs published in 2014 and 2015 failed to evaluate the assumptions of the joint synthesis. What this adds to what is knownThis meta-epidemiological study presents the largest collection of published NMAs over the past 16 years. It provides an overview of the structural characteristics and statistical methodology of 456 published networks of interventions. It shows that the statistical methods in NMA have considerably improved in all aspects and some, such as the use of appropriate methods to evaluate the plausibility of the assumptions, are now routinely performed. We conclude that the increasingly populous community of NMA methodologists is quickly advancing through the learning curve of statistical methods employed in NMA. What is the implication, what should change nowThe updated description of the structural characteristics of the published NMAs can be used to inform pragmatic simulations studies and the development of methods that are relevant to the type of networks typically found in the medical literature. Future tutorials and training should be focused on improving the methodology and reporting on items that, although they have improved, their prevalence remains low, such as the formal exploration of heterogeneity and inconsistency and the presentation of all pairwise treatment effects.

A systematic review of network meta-analyses for pharmacological treatment of common mental disorders

“…The relatively good standing of the NMAs in our review may partly reflect their relatively recent publication, consistent with Petropoulou et al ’s (2017) finding that more recently published NMAs adhere to more rigorous methodological standards 22. For instance, Petropoulou et al (2017) reported an increase in the number of NMAs discussing transitivity and inconsistency from 0% to 86% when comparing NMAs published in 2005 with those published in 2015 22.…”

“…For instance, Petropoulou et al (2017) reported an increase in the number of NMAs discussing transitivity and inconsistency from 0% to 86% when comparing NMAs published in 2005 with those published in 2015 22. In addition, although the NMAs in our review performed favourably compared with those assessed in studies of medical disorders with respect to multiple methodological features, optimal methods were not always employed, with the evaluation of consistency being a particular case in point.…”

Cognitive-Behavioral Analysis System of Psychotherapy, Drug, or Their Combination for Persistent Depressive Disorder: Personalizing the Treatment Choice Using Individual Participant Data Network Metaregression

“…When more than 2 treatment alternatives are available, network meta-analysis will take full advantage of the available data by comparing all treatments simultaneously and can elucidate the relative effectiveness among the competing alternatives. An increasingly large number of network meta-analyses has been published in the medical literature and in particular concerning mental health [19]. However, conventional meta-analysis of trial level summary data, either pairwise or in network, cannot properly assess the impact of individual characteristics.…”

Network meta-analysis: the highest level of medical evidence?

“…A recent meta-review found that 35 out of 77 (45%) network meta-analyses did not specify a plan on how to address possible effect modifiers, and the modifiers were inappropriately reported in 36 of the included network meta-analyses (47%) 16. Another recent study found that 353 out of 456 (77%) network meta-analyses contained no information or discussion of transitivity, although the evaluation of transitivity improved from 2005 to 2015 17. Review authors should specify potential effect modifiers at the protocol stage to limit publication bias and ensure appropriate reporting and discussion of transitivity.…”