{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T16:05:03Z","timestamp":1792512303563,"version":"4.5.0"},"reference-count":13,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T00:00:00Z","timestamp":1777334400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJNS"],"abstract":"<jats:p>Increasing ethnic diversity raises potential inequalities within screening programmes. In the UK, newborns are screened for CF by initially measuring IRT. Dried blood spot IRT levels above a set cut-off require follow-up testing to establish a screening result. Variation exists in IRT levels between different ethnicities and therefore impacts the number of potentially false positive results obtained from ethnic groups. Over a 4-year period, IRT data was collected, and the 99.5th centile was calculated for different ethnic groups. Significant differences were noticed between ethnic groups, and the CF outcome data over a 10-year period were then analysed to establish the effect this had on positive predictive values. The largest difference in IRT 99.5th centile values was seen between the White British and Black African groups. Positive predictive values for Black African and Indian ethnic groups were much lower than the other groups. Rather than try to incorporate ethnicity into the UK CF screening algorithm, we suggest making CF clinicians aware of the differences between different ethnic groups to inform counselling families who receive screen-positive results.<\/jats:p>","DOI":"10.3390\/ijns12020028","type":"journal-article","created":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T13:26:41Z","timestamp":1777382801000},"page":"28","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Variation in IRT in Different Ethnic Groups in England\u2014Implications for a Newborn Screening Programme for CF in Diverse Multiethnic Populations"],"prefix":"10.3390","volume":"12","author":[{"given":"Toby","family":"Greenfield","sequence":"first","affiliation":[{"name":"Blood Sciences, Portsmouth Hospitals Trust, Portsmouth PO6 3LY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-6536-6534","authenticated-orcid":false,"given":"Lesley","family":"Tetlow","sequence":"additional","affiliation":[{"name":"Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-9485-6754","authenticated-orcid":false,"given":"James R.","family":"Bonham","sequence":"additional","affiliation":[{"name":"Sheffield Children\u2019s NHS Foundation Trust, Sheffield S10 2TH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Collingwood","sequence":"additional","affiliation":[{"name":"Biochemistry Department, Alder Hey Children\u2019s NHS Foundation Trust, Liverpool L12 2AP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Wainwright","sequence":"additional","affiliation":[{"name":"Blood Sciences, Portsmouth Hospitals Trust, Portsmouth PO6 3LY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liz","family":"Robinson","sequence":"additional","affiliation":[{"name":"NHS England, Wellington House, London SE1 8UG, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dave","family":"Wright","sequence":"additional","affiliation":[{"name":"Institute of Health Research, University of Exeter, Exeter EX4 4PY, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7173-6862","authenticated-orcid":false,"given":"Beverly","family":"Hird","sequence":"additional","affiliation":[{"name":"Clinical Biochemistry, Manchester University NHS Foundation Trust, Manchester M13 9WL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tejswurree","family":"Ramgoolam","sequence":"additional","affiliation":[{"name":"Department of Chemical Pathology, Great Ormond Street Hospital for Children, London WC1N 3JH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline","family":"Griffith","sequence":"additional","affiliation":[{"name":"Specialist Laboratory Medicine, Leeds Teaching Hospitals NHS Trust, St James University Hospital, Leeds LS9 7TF, UK; <email>caroline.griffith@nhs.net<\/email>"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9203-8169","authenticated-orcid":false,"given":"Lynette","family":"Shakespeare","sequence":"additional","affiliation":[{"name":"Sheffield Children\u2019s NHS Foundation Trust, Sheffield S10 2TH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9068-3535","authenticated-orcid":false,"given":"Mehdi","family":"Mirzazadeh","sequence":"additional","affiliation":[{"name":"Department of Chemical Pathology, Epsom & St Helier University Hospitals NHS Trust, Carshalton SM5 1AA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachelle","family":"Garstone","sequence":"additional","affiliation":[{"name":"Biochemical Sciences, Synnovis, Guys & St Thomas\u2019 NHSFT, London SE1 7EH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deborah","family":"Finnerty","sequence":"additional","affiliation":[{"name":"Newborn Screening & Biochemical Genetics Department, Birmingham Women\u2019s and Children\u2019s Hospital NHS Foundation Trust, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3613-5890","authenticated-orcid":false,"given":"Nick","family":"Flynn","sequence":"additional","affiliation":[{"name":"Biochemical Genetics Unit, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge CB2 0QQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nazia","family":"Taj","sequence":"additional","affiliation":[{"name":"Clinical Biochemistry, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maya","family":"Desai","sequence":"additional","affiliation":[{"name":"Department of Respiratory Paediatrics, Birmingham Women\u2019s and Children\u2019s Hospital NHS Foundation Trust, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"484","DOI":"10.1016\/j.jcf.2022.09.012","article-title":"European CF Society Neonatal Screening Working Group (ECFS NSWG). 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(2021). Phenotypic Presentations of Cystic Fibrosis in Children of African Descent. Genes, 12.","DOI":"10.3390\/genes12030458"}],"container-title":["International Journal of Neonatal Screening"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2409-515X\/12\/2\/28\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T13:55:56Z","timestamp":1778594156000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2409-515X\/12\/2\/28"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,28]]},"references-count":13,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["ijns12020028"],"URL":"https:\/\/doi.org\/10.3390\/ijns12020028","relation":{},"ISSN":["2409-515X"],"issn-type":[{"value":"2409-515X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,28]]}}}