Response to letter: non‐vitamin‐K oral anticoagulants may not significantly reduce the risk of fatal or disabling stroke compared with warfarin
- 27 May 2020
- journal article
- letter
- Published by Wiley in European Journal of Neurology
- Vol. 27 (10), E56
- https://doi.org/10.1111/ene.14366
Abstract
We agree with Zheng and colleagues that a statistical measure of heterogeneity is an important consideration in selecting a fixed or random effects model. However, it should not be considered the sole criterion. In meta‐analyses that include small numbers of trials, such as ours, results of tests for heterogeneity should be interpreted with caution, as they may be underpowered. A fixed effects model has been advocated when meta‐analysing small number of studies (less than five trials), given the concern about inaccurate estimation of between‐study variance (1), as the estimation of τ2(between‐study variance), and therefore of μ (estimate of underlying mean effect), is highly imprecise (2).Keywords
This publication has 5 references indexed in Scilit:
- Effect of non-vitamin-K oral anticoagulants on stroke severity compared to warfarin: a meta-analysis of randomized controlled trialsEuropean Journal of Neurology, 2020
- How to interpret meta-analysis models: fixed effect and random effects meta-analysesEvidence-Based Mental Health, 2014
- Comparison of the efficacy and safety of new oral anticoagulants with warfarin in patients with atrial fibrillation: a meta-analysis of randomised trialsThe Lancet, 2014
- Confidence Interval or P-Value? Part 4 of a Series on Evaluation of Scientific PublicationsDeutsches Ärzteblatt international, 2009
- A Re-Evaluation of Random-Effects Meta-AnalysisJournal of the Royal Statistical Society Series A: Statistics in Society, 2008