{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T01:53:17Z","timestamp":1792720397434,"version":"4.5.0"},"reference-count":16,"publisher":"Springer Science and Business Media LLC","issue":"8","license":[{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100004047","name":"Karolinska Institute","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100004047","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur J Epidemiol"],"published-print":{"date-parts":[[2025,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n          <jats:p>The Swedish Multiple Sclerosis (MS) Register is a nationwide clinical tool and research database. Its generalizability to the broader MS population has not been previously assessed. We aimed to quantify the register\u2019s completeness and potential disparities between those who were included and those who were not. Using linked national registers, we identified persons with MS through December 2020 as those with \u2265\u20093 MS diagnoses in the National Patient Register. We assessed the MS register\u2019s completeness and compared characteristics between included and non-included persons, using overlap weighting to account for age differences. Among 21,320 prevalent (2020) and 7,355 incident (2011\u20132020) MS cases, the completeness of the MS register was 85% and 87%, respectively, but varied by county (67\u201394% in 2020). Prevalent cases not included in the register were older (mean 62.4 vs. 52.3 years) and more likely to have no salaried income (55.3% vs. 30.5%); had fewer years of education (20.8% vs. 12.0% with \u2264\u20099 years); more often been hospitalized (41.5% vs. 32.2%); and collected more unique prescribed drugs (median 7 vs. 5 drugs per year). Incident cases were also older at first MS diagnosis (mean 50.3 vs. 39.2 years). All differences were attenuated by adjusting for age, although disparities remained. The Swedish MS Register demonstrates high completeness, but may not fully represent older persons with MS, those diagnosed later in life, and those of lower socioeconomic status. These limitations should be considered when interpreting findings based on the register\u2019s data.<\/jats:p>","DOI":"10.1007\/s10654-025-01276-z","type":"journal-article","created":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T07:52:25Z","timestamp":1753343545000},"page":"905-913","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Completeness and generalizability of the Swedish MS register"],"prefix":"10.1007","volume":"40","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4710-6326","authenticated-orcid":false,"given":"Peter","family":"Alping","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5735-9626","authenticated-orcid":false,"given":"Thomas","family":"Frisell","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6924-8798","authenticated-orcid":false,"given":"Anna","family":"He","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7386-6732","authenticated-orcid":false,"given":"Jan","family":"Hillert","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0030-0236","authenticated-orcid":false,"given":"Katharina","family":"Fink","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9081-1522","authenticated-orcid":false,"given":"Kyla A.","family":"McKay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,7,24]]},"reference":[{"key":"1276_CR1","unstructured":"Fink K. Swedish Multiple Sclerosis Register [Internet]. 2001. Available from: http:\/\/www.neuroreg.se\/"},{"issue":"199","key":"1276_CR2","doi-asserted-by":"publisher","first-page":"11","DOI":"10.1111\/ane.12425","volume":"132","author":"J Hillert","year":"2015","unstructured":"Hillert J, Stawiarz L. The Swedish MS registry \u2013 clinical support tool and scientific resource. Acta Neurol Scand. 2015;132(199):11\u20139.","journal-title":"Acta Neurol Scand"},{"key":"1276_CR3","unstructured":"Hillert J. The Swedish Multiple Sclerosis Register - Yearly Report 2023 [Internet]. 2024 [cited 2024 Aug 14]. Available from: https:\/\/www.neuroreg.se\/media\/mozj0en2\/multipel-skleros-%C3%A5rsrapport-2023.pdf"},{"key":"1276_CR4","unstructured":"Jomer C. T\u00e4ckningsgrader f\u00f6r Nationella kvalitetsregister 2020 [Internet]. Socialstyrelsen; 2020 Dec [cited 2024 Feb 28]. (T\u00e4ckningsgrader f\u00f6r Nationella kvalitetsregister). Available from: https:\/\/www.socialstyrelsen.se\/globalassets\/sharepoint-dokument\/artikelkatalog\/statistik\/2020-12-7049.pdf"},{"issue":"2","key":"1276_CR5","doi-asserted-by":"publisher","first-page":"230","DOI":"10.1097\/EDE.0000000000000948","volume":"30","author":"P Alping","year":"2019","unstructured":"Alping P, Piehl F, Langer-Gould A, Frisell T, COMBAT-MS Study Group. Validation of the Swedish multiple sclerosis register: further improving a resource for pharmacoepidemiologic evaluations. Epidemiology. 2019;30(2):230\u20133.","journal-title":"Epidemiology"},{"issue":"6","key":"1276_CR6","doi-asserted-by":"publisher","first-page":"680","DOI":"10.1111\/ane.13514","volume":"144","author":"C Teljas","year":"2021","unstructured":"Teljas C, Bostr\u00f6m I, Marrie RA, Landtblom AM, Manouchehrinia A, Hillert J, et al. Validating the diagnosis of multiple sclerosis using Swedish administrative data in V\u00e4rmland County. Acta Neurol Scand. 2021;144(6):680\u20136.","journal-title":"Acta Neurol Scand"},{"issue":"11","key":"1276_CR7","doi-asserted-by":"publisher","first-page":"659","DOI":"10.1007\/s10654-009-9350-y","volume":"24","author":"JF Ludvigsson","year":"2009","unstructured":"Ludvigsson JF, Otterblad-Olausson P, Pettersson BU, Ekbom A. The Swedish personal identity number: possibilities and pitfalls in healthcare and medical research. Eur J Epidemiol. 2009;24(11):659\u201367.","journal-title":"Eur J Epidemiol"},{"key":"1276_CR8","unstructured":"Socialstyrelsen. National Patient Register [Internet]. Socialstyrelsen. Available from: https:\/\/www.socialstyrelsen.se\/en\/statistics-and-data\/registers\/national-patient-register\/"},{"key":"1276_CR9","doi-asserted-by":"publisher","first-page":"450","DOI":"10.1186\/1471-2458-11-450","volume":"11","author":"JF Ludvigsson","year":"2011","unstructured":"Ludvigsson JF, Andersson E, Ekbom A, Feychting M, Kim JL, Reuterwall C, et al. External review and validation of the Swedish National inpatient register. BMC Public Health. 2011;11:450.","journal-title":"BMC Public Health"},{"key":"1276_CR10","unstructured":"SCB. Total Population Register [Internet]. Available from: https:\/\/www.scb.se\/vara-tjanster\/bestall-data-och-statistik\/register\/registret-over-totalbefolkningen-rtb\/"},{"issue":"2","key":"1276_CR11","doi-asserted-by":"publisher","first-page":"125","DOI":"10.1007\/s10654-016-0117-y","volume":"31","author":"JF Ludvigsson","year":"2016","unstructured":"Ludvigsson JF, Almqvist C, Bonamy AKE, Ljung R, Micha\u00eblsson K, Neovius M, et al. Registers of the Swedish total population and their use in medical research. Eur J Epidemiol. 2016;31(2):125\u201336.","journal-title":"Eur J Epidemiol"},{"key":"1276_CR12","unstructured":"SCB. Income and Taxation Register [Internet]. Available from: https:\/\/www.scb.se\/vara-tjanster\/bestall-data-och-statistik\/register\/inkomst\u2013och-taxeringsregistret-iot\/"},{"key":"1276_CR13","unstructured":"SCB. LISA [Internet]. Available from: https:\/\/www.scb.se\/vara-tjanster\/bestall-data-och-statistik\/register\/lisa\/"},{"issue":"4","key":"1276_CR14","doi-asserted-by":"publisher","first-page":"423","DOI":"10.1007\/s10654-019-00511-8","volume":"34","author":"JF Ludvigsson","year":"2019","unstructured":"Ludvigsson JF, Svedberg P, Ol\u00e9n O, Bruze G, Neovius M. The longitudinal integrated database for health insurance and labour market studies (LISA) and its use in medical research. Eur J Epidemiol. 2019;34(4):423\u201337.","journal-title":"Eur J Epidemiol"},{"key":"1276_CR15","doi-asserted-by":"publisher","unstructured":"Thomas LE, Li F, Pencina MJ. Overlap Weighting: A Propensity Score Method That Mimics Attributes of a Randomized Clinical Trial. JAMA [Internet]. 2020 Jun 16 [cited 2024 Dec 10];323(23):2417\u20138. Available from: https:\/\/doi.org\/10.1001\/jama.2020.7819","DOI":"10.1001\/jama.2020.7819"},{"issue":"12","key":"1276_CR16","doi-asserted-by":"publisher","first-page":"723","DOI":"10.1038\/s41582-022-00735-5","volume":"18","author":"R Dobson","year":"2022","unstructured":"Dobson R, Rice DR, D\u2019hooghe M, Horne R, Learmonth Y, Mateen FJ, et al. Social determinants of health in multiple sclerosis. Nat Rev Neurol. 2022;18(12):723\u201334.","journal-title":"Nat Rev Neurol"}],"container-title":["European Journal of Epidemiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10654-025-01276-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s10654-025-01276-z\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10654-025-01276-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,9,7]],"date-time":"2025-09-07T21:23:06Z","timestamp":1757280186000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s10654-025-01276-z"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,24]]},"references-count":16,"journal-issue":{"issue":"8","published-print":{"date-parts":[[2025,8]]}},"alternative-id":["1276"],"URL":"https:\/\/doi.org\/10.1007\/s10654-025-01276-z","relation":{},"ISSN":["0393-2990","1573-7284"],"issn-type":[{"value":"0393-2990","type":"print"},{"value":"1573-7284","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,24]]},"assertion":[{"value":"31 January 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"1 July 2025","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"24 July 2025","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"All authors have previously used data from the Swedish MS register in their studies. PA, TF, and AH have no other disclosures. JH is the former register holder for the Swedish MS register and has additionally received honoraria for serving on advisory boards for Biogen, Bristol-Myers-Squibb, Janssen, Merck KGaA, Novartis, Sandoz, and Sanofi-Genzyme, received speaker fees from Biogen, Janssen, Novartis, Merck, Teva, Sandoz, and Sanofi-Genzyme, and served as P.I. for projects sponsored by, or received unrestricted research support from, Biogen, Bristol-Myers-Squibb, EMD-Serono, Janssen, Merck KGaA, Novartis, Roche, and Sanofi-Genzyme. KF is the current register holder for the Swedish MS register and has received research support from Merck, UCB, Amicus, and Novartis. KAM has received speaker honoraria from Biogen (2023) and Sanofi (2022).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Swedish Ethical Review Authority (reference: 2021\u201302384 and 2023-07906-02).","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}}]}}