ArticleEcology and evolution2020
Ignoring non-English-language studies may bias ecological meta-analyses.
Article in Ecology and evolution, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 56 papers, 12 of them syntheses that pooled it.
What it found
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Who cites it
56 citing papers in PubMed, 12 syntheses or guidelines pooled it.
- The evidence base for ranger patrol effectiveness in conservation and how to improve it.Biological reviews of the Cambridge Philosophical Society · 2026Pooled it
- Semaglutide-associated risk of nonarteritic anterior ischemic optic neuropathy in patients with type 2 diabetes: A systematic review and meta-analysis of observational studies.PLoS medicine · 2026 · on this mapPooled it
- Neuropsychiatric disorders in children of mothers with polycystic ovary syndrome: a systematic review and meta-analysis.BMC psychiatry · 2026Pooled it
- No Evidence for Pace of Life Evolution Along Elevational Gradients in Squamate Reptiles.Ecology letters · 2026Pooled it
- Omalizumab for pediatric allergic asthma: evidence-based insights on efficacy and safety from a meta-analysis of randomized trials.Frontiers in pharmacology · 2026Pooled it
- The use of Language ENvironment Analysis in autism research: A systematic review.Autism : the international journal of research and practice · 2025Pooled it
- Emotional factor matters in language learning? A meta-analysis of emotional intelligence on language achievement.Frontiers in psychology · 2025Pooled it
- Climate change effects on ecosystem services: Disentangling drivers of mixed responses.PloS one · 2025Pooled it
- Global meta-analysis shows reduced quality of food crops under inadequate animal pollination.Nature communications · 2023Pooled it
- Climate change and the global redistribution of biodiversity: substantial variation in empirical support for expected range shifts.Environmental evidence · 2023Pooled it
- A meta-analysis of the ecological and economic outcomes of mangrove restoration.Nature communications · 2021Pooled it
- A multiyear systematic survey of the quality of reporting for randomised trials in dentistry, neurology and geriatrics published in journals of Spain and Latin America.BMC medical research methodology · 2021Pooled it
- Biases in butterfly survey effort and patterns of protocol used across biogeographic regions.Ecological applications : a publication of the Ecological Society of America · 2026Review
- Thinking Outside the Black Box: Seven Guidelines for GenAI Use in the Ecological Sciences.Ecology and evolution · 2026Article
- A global database of West Nile virus host prevalence and competence.Scientific data · 2026Article
- Interventions for Improving Leisure for Older Adults on the Palliative Pathway Living With Advanced Cancer: A Qualitative Systematic Review.The British journal of occupational therapy · 2026Review
- Enabling conditions for conservation on Indigenous and community lands.Conservation biology : the journal of the Society for Conservation Biology · 2026Review
- Behavioural plasticity of a pest species may aggravate global wheat yield loss under climate change.Nature communications · 2025Article
- Petiole mechanics of coexisting tree species in a warm-temperate forest understory in relation to leaf size, leaf habit, and leaf form.Oecologia · 2025Article
- Spanish-language text classification for environmental evidence synthesis using multilingual pre-trained models.Environmental evidence · 2025Article
Corrections and comments
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Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Meta-analysis plays a crucial role in syntheses of quantitative evidence in ecology and biodiversity conservation. The reliability of estimates in meta-analyses strongly depends on unbiased sampling of primary studies. Although earlier studies have explored potential biases in ecological meta-analyses, biases in reported statistical results and associated study characteristics published in different languages have never been tested in environmental sciences. We address this knowledge gap by systematically searching published meta-analyses and comparing effect-size estimates between English- and Japanese-language studies included in existing meta-analyses. Of the 40 published ecological meta-analysis articles authored by those affiliated to Japanese institutions, we find that three meta-analysis articles searched for studies in the two languages and involved sufficient numbers of English- and Japanese-language studies, resulting in four eligible meta-analyses (i.e., four meta-analyses conducted in the three meta-analysis articles). In two of the four, effect sizes differ significantly between the English- and Japanese-language studies included in the meta-analyses, causing considerable changes in overall mean effect sizes and even their direction when Japanese-language studies are excluded. The observed differences in effect sizes are likely attributable to systematic differences in reported statistical results and associated study characteristics, particularly taxa and ecosystems, between English- and Japanese-language studies. Despite being based on a small sample size, our findings suggest that ignoring non-English-language studies may bias outcomes of ecological meta-analyses, due to systematic differences in study characteristics and effect-size estimates between English- and non-English languages. We provide a list of actions that meta-analysts could take in the future to reduce the risk of language bias.
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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.