Ignoring non‐English‐language studies may bias ecological meta‐analyses

作者：Ko Konno, Munemitsu Akasaka, Chieko Koshida, Naoki Katayama, Noriyuki Osada, Rebecca Spake, Tatsuya Amano · 发表于：Ecology and Evolution · 年份：2020 · DOI：10.1002/ece3.6368 · 被引用次数：248 · 研究领域：Species Distribution and Climate Change、Ecology and Vegetation Dynamics Studies、Rangeland and Wildlife Management

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 ecosys...