Based on the rigorous systematicity assumed in systematic review methodology, it is no surprise that a prominent review such as Macaro et al.'s (2018) on English medium instruction (EMI) has been used as a basis for subsequent EMI research. However, in this article, we explore the ways in which the focus of systematic reviews can be necessarily narrowed and how this poses a risk to research when readers perceive them as offering definitive conclusions on all aspects of a subject. This article addresses two significant trends in applied linguistics. First, systematic review – that is, the use of formalised systems when reviewing literature – has become far more prominent and therefore more impactful than traditional reviews as a methodology (Chong & Plonsky, 2023). Second, there has been an explosive growth in interest in EMI research (Curle et al., 2024). There are further parallels between the two trends, given that both systematic review and EMI are umbrella terms that cover a wide range of research types. As we will see, there is perhaps more disagreement over how to conduct a systematic review than lay readers would suspect. Similarly, EMI is a broader field of research than appears in its most prominent systematic review article. Studies into EMI have explored policy, language learning, the effect on subject knowledge, attitudes towards EMI, ownership of English, and so on. Thus, while EMI is a growingly recognised field of study, it is not always clear what it means to ‘study EMI’.

中文翻译：

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系统评价，系统性偏倚？EMI 研究的一个例子


基于系统评价方法中假设的严格系统性，Macaro et al.（2018 年）关于英语教学 （EMI） 的著名评论被用作后续 EMI 研究的基础也就不足为奇了。然而，在本文中，我们探讨了系统综述的关注点必然缩小的方式，以及当读者认为系统综述对主题的各个方面提供了明确的结论时，这如何对研究构成风险。本文讨论了应用语言学的两个重要趋势。首先，系统评价 - 即在审查文献时使用正式的系统 - 已经变得比传统的审查方法更加突出，因此更具影响力（Chong & Plonsky）（Chong & Plonsky，2023）。其次，人们对 EMI 研究的兴趣呈爆炸式增长（Curle et al.， 2024）。鉴于系统评价和 EMI 都是涵盖广泛研究类型的总称，这两个趋势之间还有进一步的相似之处。正如我们将看到的，关于如何进行系统评价的分歧可能比非专业读者想象的要多。同样，EMI 是一个比其最著名的系统评价文章中出现的更广泛的研究领域。对 EMI 的研究探讨了政策、语言学习、对学科知识的影响、对 EMI 的态度、英语所有权等。因此，虽然 EMI 是一个越来越受认可的研究领域，但 “研究 EMI ”的含义并不总是很清楚。