ArticleResearch synthesis methods2019
Pitfalls of using the risk ratio in meta-analysis.
Article in Research synthesis methods, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 39 papers, 20 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
39 citing papers in PubMed, 20 syntheses or guidelines pooled it.
- Efficacy of home treatment and inpatient treatment for children and adolescents in psychiatric crisis: a systematic review and meta-analysis.European child & adolescent psychiatry · 2026Pooled it
- The comparative effects of prenatal exposure to methadone versus buprenorphine for opioid use disorder on neonatal outcomes: a systematic review and meta-analysis.BMC pregnancy and childbirth · 2026Pooled it
- Vitamin D supplementation to prevent acute respiratory infections: systematic review and meta-analysis of stratified aggregate data.The lancet. Diabetes & endocrinology · 2025Pooled it
- Effectiveness of preconception weight loss interventions on fertility in women: a systematic review and meta-analysis.Fertility and sterility · 2024Pooled it
- Network Meta-Analysis Indicates Superior Effects of Omega-3 Polyunsaturated Fatty Acids in Preventing the Transition to Psychosis in Individuals at Clinical High-Risk.The international journal of neuropsychopharmacology · 2024Pooled it
- Antipsychotic dose, dopamine D2 receptor occupancy and extrapyramidal side-effects: a systematic review and dose-response meta-analysis.Molecular psychiatry · 2023Pooled it
- On the Q statistic with constant weights in meta-analysis of binary outcomes.BMC medical research methodology · 2023Pooled it
- Exceedance Probabilities of Log-normal Distributions for One Group, Two Groups, and Meta-analysis of Multiple Two-group Studies, With Application to Analyses of Prolonged Times to Tracheal Extubation.Journal of medical systems · 2023Pooled it
- The normality assumption on between-study random effects was questionable in a considerable number of Cochrane meta-analyses.BMC medicine · 2023Pooled it
- Pooled it
- Prolonged cardiac monitoring for stroke prevention: A systematic review and meta-analysis of randomized-controlled clinical trials.European stroke journal · 2023Pooled it
- Performance of several types of beta-binomial models in comparison to standard approaches for meta-analyses with very few studies.BMC medical research methodology · 2022Pooled it
- Pharmacological and dietary-supplement treatments for autism spectrum disorder: a systematic review and network meta-analysis.Molecular autism · 2022Pooled it
- Oral Antihypertensives for Nonsevere Pregnancy Hypertension: Systematic Review, Network Meta- and Trial Sequential Analyses.Hypertension (Dallas, Tex. : 1979) · 2022Pooled it
- Effect of adjunctive vitamin C, glucocorticoids, and vitamin B1 on longer-term mortality in adults with sepsis or septic shock: a systematic review and a component network meta-analysis.Intensive care medicine · 2022Pooled it
- Efficacy and safety of Keluoxin capsule in combination with Western medicine for diabetic kidney disease: A systematic review and meta-analysis.Frontiers in pharmacology · 2022Pooled it
- Examination of Dosing of Antipsychotic Drugs for Relapse Prevention in Patients With Stable Schizophrenia: A Meta-analysis.JAMA psychiatry · 2021Pooled it
- Methodological assessment of systematic reviews and meta-analyses on COVID-19: A meta-epidemiological study.Journal of evaluation in clinical practice · 2021Pooled it
- Multivariate meta-analysis of critical care meta-analyses: a meta-epidemiological study.BMC medical research methodology · 2021Pooled it
- Estimation in meta-analyses of response ratios.BMC medical research methodology · 2020Pooled it
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
Abstract
For meta-analysis of studies that report outcomes as binomial proportions, the most popular measure of effect is the odds ratio (OR), usually analyzed as log(OR). Many meta-analyses use the risk ratio (RR) and its logarithm because of its simpler interpretation. Although log(OR) and log(RR) are both unbounded, use of log(RR) must ensure that estimates are compatible with study-level event rates in the interval (0, 1). These complications pose a particular challenge for random-effects models, both in applications and in generating data for simulations. As background, we review the conventional random-effects model and then binomial generalized linear mixed models (GLMMs) with the logit link function, which do not have these complications. We then focus on log-binomial models and explore implications of using them; theoretical calculations and simulation show evidence of biases. The main competitors to the binomial GLMMs use the beta-binomial (BB) distribution, either in BB regression or by maximizing a BB likelihood; a simulation produces mixed results. Two examples and an examination of Cochrane meta-analyses that used RR suggest bias in the results from the conventional inverse-variance-weighted approach. Finally, we comment on other measures of effect that have range restrictions, including risk difference, and outline further research.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.