METAN: Stata module for fixed and random effects meta-analysis

Published On 2022/10/12

Meta-analysis is a statistical technique for combining results from multiple independent studies, with the aim of estimating a single overall effect. The routines in this package provide facilities to conduct meta-analyses of binary (event) or continuous data from two groups, or intervention effect estimates with corresponding standard errors or confidence intervals. This is an updated version of metan as published in Stata Journal Issue 8, and prior to that in STB-44, authored by Michael J Bradburn, Jonathan J Deeks and Douglas G Altman. Updates include a wide range of random-effects models; cumulative and influence analysis; meta-analysis of proportions; and better handling of heterogeneity, continuity correction and returned values. The routine for constructing forest plots has been separated off (‘forestplot’ command) and hugely extended; extremely flexible and generalised forest plots may now be produced. Also included is an “immediate” command ‘metani’, which accepts numlists or matrices as input rather than variables in memory; the ‘metannt’ program for binary data, which displays estimated intervention effects in terms of the absolute reduction in risk and number needed to treat; and the ‘labbe’ program which produces L'Abbe plots to examine whether the assumption of a common odds ratio, risk ratio or risk difference is reasonable. Further information on this package, including validation scripts, may be found at https://github.com/UCL/metan; and a description of available Stata meta-analysis commands may be found at http://www.stata.com/support/faqs/stat/meta.html.

Authors

Douglas G Altman

Douglas G Altman

University of Oxford

H-Index

281

Research Interests

biostatistics

statistics

medical statistics

University Profile Page

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

H-Index

183

Research Interests

evidence synthesis

meta-analysis

systematic review

health technology assessment

biostatistics

University Profile Page

Jonathan Sterne

Jonathan Sterne

University of Bristol

H-Index

147

Research Interests

Medical Statistics

HIV

Evidence Synthesis

Epidemiology

Causal Inference

University Profile Page

Other Articles from authors

Jonathan Sterne

Jonathan Sterne

University of Bristol

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Prof Julian Higgins

Prof Julian Higgins

University of Bristol

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Jonathan Sterne

Jonathan Sterne

University of Bristol

The Lancet HIV

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Prof Julian Higgins

Prof Julian Higgins

University of Bristol

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Prof Julian Higgins

Prof Julian Higgins

University of Bristol

Heat impacts on human health in the Western Pacific Region: an umbrella review

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Jonathan Sterne

Jonathan Sterne

University of Bristol

JAMA

Prostate-Specific Antigen Screening and 15-Year Prostate Cancer Mortality: A Secondary Analysis of the CAP Randomized Clinical Trial

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Douglas G Altman

Douglas G Altman

University of Oxford

Journal of the College of Community Physicians of Sri Lanka

Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): Explanation and Elaboration: a Korean translation

ImportanceMendelian randomization (MR) studies use genetic variation associated with modifiable exposures to assess their possible causal relationship with outcomes and aim to reduce potential bias from confounding and reverse causation.ObjectiveTo develop the STROBE-MR Statement as a stand-alone extension to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guideline for the reporting of MR studies.Design, Setting, and ParticipantsThe development of the STROBE-MR Statement followed the Enhancing the Quality and Transparency of Health Research (EQUATOR) framework guidance and used the STROBE Statement as a starting point to draft a checklist tailored to MR studies. The project was initiated in 2018 by reviewing the literature on the reporting of instrumental variable and MR studies. A group of 17 experts, including MR methodologists, MR study design …

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

Efficacy of PD-1/PD-L1 immunotherapy on brain metastatic non-small-cell lung cancer and treatment-related adverse events: a systematic review

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Jonathan Sterne

Jonathan Sterne

University of Bristol

medRxiv

Comparative safety and effectiveness of Pfizer BA. 4-5 versus Sanofi during the spring 2023 COVID-19 booster vaccination programme in England: a matched cohort study in …

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Jonathan Sterne

Jonathan Sterne

University of Bristol

AIDS

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ObjectiveInterruptions in care of people with HIV (PWH) on antiretroviral therapy (ART) are associated with

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

Methodological review of NMA bias concepts provides groundwork for the development of a list of concepts for potential inclusion in a new risk of bias tool for network meta …

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Jonathan Sterne

Jonathan Sterne

University of Bristol

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Jonathan Sterne

Jonathan Sterne

University of Bristol

Environment International

A tool to assess risk of bias in non-randomized follow-up studies of exposure effects (ROBINS-E)

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Prof Julian Higgins

Prof Julian Higgins

University of Bristol

Environment International

A tool to assess risk of bias in non-randomized follow-up studies of exposure effects (ROBINS-E)

BackgroundObservational epidemiologic studies provide critical data for the evaluation of the potential effects of environmental, occupational and behavioural exposures on human health. Systematic reviews of these studies play a key role in informing policy and practice. Systematic reviews should incorporate assessments of the risk of bias in results of the included studies.ObjectiveTo develop a new tool, Risk Of Bias In Non-randomized Studies - of Exposures (ROBINS-E) to assess risk of bias in estimates from cohort studies of the causal effect of an exposure on an outcome.Methods and resultsROBINS-E was developed by a large group of researchers from diverse research and public health disciplines through a series of working groups, in-person meetings and pilot testing phases. The tool aims to assess the risk of bias in a specific result (exposure effect estimate) from an individual observational study that …

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

European Journal of Epidemiology

Meta-regression of genome-wide association studies to estimate age-varying genetic effects

Fixed-effect meta-analysis has been used to summarize genetic effects on a phenotype across multiple Genome-Wide Association Studies (GWAS) assuming a common underlying genetic effect. Genetic effects may vary with age (or other characteristics), and not allowing for this in a GWAS might lead to bias. Meta-regression models between study heterogeneity and allows effect modification of the genetic effects to be explored. The aim of this study was to explore the use of meta-analysis and meta-regression for estimating age-varying genetic effects on phenotypes. With simulations we compared the performance of meta-regression to fixed-effect and random-effects meta-analyses in estimating (i) main genetic effects and (ii) age-varying genetic effects (SNP by age interactions) from multiple GWAS studies under a range of scenarios. We applied meta-regression on publicly available summary data to estimate the …

Jonathan Sterne

Jonathan Sterne

University of Bristol

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Jonathan Sterne

Jonathan Sterne

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With the approval of NHS England, we quantified associations between COVID-19 diagnosis and cardiovascular diseases in different vaccination and variant eras using linked electronic health records for~ 40% of the English population. We defined a ‘pre-vaccination’cohort (18,210,937 people) in the wild-type/Alpha variant eras (January 2020-June 2021), and ‘vaccinated’and ‘unvaccinated’cohorts (13,572,399 and 3,161,485 people respectively) in the Delta variant era (June-December 2021). The incidence of each arterial thrombotic, venous thrombotic and other cardiovascular outcomes was substantially elevated during weeks 1-4 after COVID-19, compared with before or without COVID-19, but less markedly elevated in time periods beyond week 4. Hazard ratios were higher after hospitalized than non-hospitalized COVID-19 and higher in the pre-vaccination and unvaccinated than the vaccinated cohort. COVID-19 vaccination reduces the risk of cardiovascular events after COVID-19 infection. People who had COVID-19 before being vaccinated are at higher risk of cardiovascular events for at least two years.

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

arXiv preprint arXiv:2402.18298

Mapping between measurement scales in meta-analysis, with application to measures of body mass index in children

Quantitative evidence synthesis methods aim to combine data from multiple medical trials to infer relative effects of different interventions. A challenge arises when trials report continuous outcomes on different measurement scales. To include all evidence in one coherent analysis, we require methods to `map' the outcomes onto a single scale. This is particularly challenging when trials report aggregate rather than individual data. We are motivated by a meta-analysis of interventions to prevent obesity in children. Trials report aggregate measurements of body mass index (BMI) either expressed as raw values or standardised for age and sex. We develop three methods for mapping between aggregate BMI data using known relationships between individual measurements on different scales. The first is an analytical method based on the mathematical definitions of z-scores and percentiles. The other two approaches involve sampling individual participant data on which to perform the conversions. One method is a straightforward sampling routine, while the other involves optimization with respect to the reported outcomes. In contrast to the analytical approach, these methods also have wider applicability for mapping between any pair of measurement scales with known or estimable individual-level relationships. We verify and contrast our methods using trials from our data set which report outcomes on multiple scales. We find that all methods recreate mean values with reasonable accuracy, but for standard deviations, optimization outperforms the other methods. However, the optimization method is more likely to underestimate standard deviations …

Prof Julian Higgins

Prof Julian Higgins

University of Bristol

arXiv preprint arXiv:2401.01806

A complex meta-regression model to identify effective features of interventions from multi-arm, multi-follow-up trials

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Jonathan Sterne

Jonathan Sterne

University of Bristol

Journal of viral hepatitis

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