The many languages of developmental disability research

As part of editorial actions we have been undertaking to promote diversity, equity, and inclusion, we have also placed emphasis on languages. With help from both authors and societies, we have been able to publish excellent translations of abstracts and manuscripts into the languages of their varied communities (https://www.macke ith.co.uk/journ al/trans lated mater ial/). We also have podcasts in several languages, which are being watched by many viewers from all over the world. We have adapted our Author Guidelines to require authors of systematic literature reviews to attempt to identify and assess for eligibility all possibly relevant articles (irrespective of language of publication) to optimize applicability and usefulness of the reviews. In line with the JBI, Cochrane Collaboration, and Campbell Collaboration, we think that limiting searching to databases that contain only or predominantly English language records, even without language restrictions, may miss relevant studies, overlook meaningful cultural contexts, and enhance existing bias. In agreement with editorial colleagues at other journals, we consider using a machine translation engine to translate nonEnglish papers as acceptable practice for screening and assessing suitability, as well as translation through dedicated platforms (full translation is often unnecessary for this purpose). Our authors' compliance and feedback have been very good so far. But their effort and rigour in looking for research published in any language has yielded dramatically few more eligible primary studies. Similarly, among 128 metaanalyses within the Cochrane Child Health register that searched for nonEnglish language studies, these were included in only 12% of reviews, representing less than 5% of included studies. Multiple factors can account for the apparent predominance of Englishlanguage research papers in our field. English has arguably become the ultimate language for research communication in many fields; there are relative exceptions, such as applied sciences and the humanities, and closer to us psychiatry and orthopaedics, but these too have been aligning to the same trend. This is perhaps not due to inherent qualities of this language but to some historical developments. Other idioms served as lingua franca in the past, including Greek, Latin, Arabic, and Chinese, enabling scholars from different places and cultures to exchange findings and ideas, produce and share knowledge. By the end of the 20th century, English emerged as a major tongue of science in an international context of multilingualism, gradually surpassing German and French, and distancing Russian and Japanese, to achieve an unrivalled position for peerreviewed papers. This implies that most researchers who are not native Englishspeakers publish in English. 4 Doing so has become indispensable for recognition both internationally and locally, because bibliometric indicators that are heavily if indirectly influenced by language of publication are being used to evaluate individuals, projects, departments, and institutions. Many periodicals that originally published papers in other languages have now commuted to English only. The authors of the Cochrane Child Health register mentioned above suggested that including nonEnglish language studies rarely impacted the results and conclusions of systematic reviews, but also admitted to some limitations of their methodology, leading to lack of consideration of the clinical significance of reported change, and of studies that escaped reviewers' search strategy. There remain challenges with indexing some nonEnglish language papers in databases that are supposed to offer comprehensive indexing to serve the research community. For example, many journals meeting the Latindex editorial quality criteria are not indexed in global databases, which reduces the international discoverability of their articles. Admittedly, a proportion of journals do not comply with requirements relating to editorial management, content (including scientific quality), and presentation. As members of a research community, we will keep encouraging and monitoring progress in this respect, keenly aware of the importance of multiplicity of perspectives, including cultural and languagerelated ideas, to move the field of paediatric neurology and childhoodonset disability forward.