{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T02:43:54Z","timestamp":1790390634727,"version":"4.1.0"},"reference-count":67,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,9,27]],"date-time":"2023-09-27T00:00:00Z","timestamp":1695772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Research concerned with children and young people who have neurodevelopmental disabilities (ND) in relation to early language acquisition usually involves comparisons with matched group(s) of typically developing individuals. In these studies, several important and complex issues need to be addressed. Three major issues are related to: (1) the choice of a variables on which to carry out group matching; (2) recruiting children into the study; and (3) the statistical analysis of the data. To assist future research on this topic, we discuss each of these three issues and provide recommendations about what we believe to be the best course of action. To provide a comprehensive review of the methodological issues, we draw on research beyond the topic of early language acquisition. Our overall aim is to contribute to research that considers questions about delay or differences in development patterns of development and about identifying potentially causal variables.<\/jats:p>","DOI":"10.3390\/brainsci13101377","type":"journal-article","created":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T01:42:12Z","timestamp":1695865332000},"page":"1377","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["The Perfect Match! A Review and Tutorial on Issues Related to Matching Groups in Investigations of Children with Neurodevelopmental Conditions"],"prefix":"10.3390","volume":"13","author":[{"given":"David","family":"Messer","sequence":"first","affiliation":[{"name":"Childhood and Youth Research Cluster, Faculty of Wellbeing, Education & Language Studies, Open University, Milton Keynes MK7 6AA, UK"},{"name":"Department of Language and Communication Science, City, University of London, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5422-4358","authenticated-orcid":false,"given":"Lucy A.","family":"Henry","sequence":"additional","affiliation":[{"name":"Department of Language and Communication Science, City, University of London, London EC1V 0HB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henrik","family":"Danielsson","sequence":"additional","affiliation":[{"name":"Department of Behavioural Sciences and Learning, Link\u00f6ping University, 581 83 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,27]]},"reference":[{"key":"ref_1","unstructured":"Burack, J.A., Hodapp, R.M., and Zigler, E. 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