{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T16:11:34Z","timestamp":1789747894149,"version":"4.0.1"},"reference-count":36,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Epileptic Disorders"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Approximately 30% of individuals with epilepsy are drug\u2010resistant, suffering low quality of life and should be evaluated for other treatment modalities. Drug\u2010resistant epilepsy has no specific diagnostic code, making identification in national healthcare registers challenging and limiting epidemiological research based on register data.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>To define our cohort, we used 1320 individuals from the Swedish National Epilepsy Surgery Register (SNESUR) as index individuals. Each index individual was matched with up to 17 individuals with epilepsy of similar age and diagnosis year in the Swedish National Patient Register. After excluding all SNESUR individuals, the study cohort consisted of 21\u2009393 individuals, a cohort broadly representative of the general epilepsy population. Data on diagnoses, procedures, healthcare contacts, and dispensed antiseizure medications were obtained from national registers. A distance\u2010based ranking algorithm was developed and validated against medical records. Three machine\u2010learning classifiers were then trained and tested using a proxy of the International League Against Epilepsy definition of drug\u2010resistant epilepsy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The ranking algorithm showed high performance for identifying drug\u2010resistant epilepsy, with a positive predictive value (PPV) of 86.2% (95% CI: 0.81\u20130.90). Out of the three machine\u2010learning classifiers, Gradient Boosting Machine achieved the highest F1\u2010score of 0.762 (along with PPV\u2009=\u20090.781, sensitivity\u2009=\u20090.744, specificity\u2009=\u20090.820, area under the precision\u2010recall curve\u2009=\u20090.858). The most significant variables found were \u201ctotal visits to outpatient clinic due to epilepsy,\u201d \u201cage of onset of epilepsy,\u201d \u201ctotal admissions due to epilepsy,\u201d and \u201ctotal days of admission due to epilepsy.\u201d<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Both the ranking algorithm and machine\u2010learning approaches showed good performance in register\u2010based phenotyping of drug\u2010resistant epilepsy using routinely collected register data, supporting their use in epidemiologic research.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/epd2.70389","type":"journal-article","created":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T15:59:59Z","timestamp":1789747199000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Identifying drug\u2010resistant epilepsy using Swedish National Patient Registry data"],"prefix":"10.1002","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9036-3661","authenticated-orcid":false,"given":"Matilda","family":"Modigh","sequence":"first","affiliation":[{"name":"Astrid Lindgren Children's Hospital Karolinska University Hospital  Stockholm Sweden"},{"name":"Department of Women's and Children's Health Karolinska Institutet  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-6912-2105","authenticated-orcid":false,"given":"Elina","family":"Tayebi","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science KTH, Royal Institute of Technology  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1183-150X","authenticated-orcid":false,"given":"Ronny","family":"Wickstr\u00f6m","sequence":"additional","affiliation":[{"name":"Astrid Lindgren Children's Hospital Karolinska University Hospital  Stockholm Sweden"},{"name":"Department of Women's and Children's Health Karolinska Institutet  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5807-3438","authenticated-orcid":false,"given":"Cecilia","family":"Bartholdson","sequence":"additional","affiliation":[{"name":"Astrid Lindgren Children's Hospital Karolinska University Hospital  Stockholm Sweden"},{"name":"Department of Women's and Children's Health Karolinska Institutet  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8044-9195","authenticated-orcid":false,"given":"Arvind","family":"Kumar","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science KTH, Royal Institute of Technology  Stockholm Sweden"},{"name":"Science for Life Laboratory  Stockholm Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8189-4098","authenticated-orcid":false,"given":"Hel\u00e9ne","family":"Sundelin","sequence":"additional","affiliation":[{"name":"Department of Women's and Children's Health Karolinska Institutet  Stockholm Sweden"},{"name":"National Centre for Epilepsy Oslo University Hospital  Oslo Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,18]]},"reference":[{"issue":"10172","key":"e_1_2_13_2_1","doi-asserted-by":"crossref","first-page":"689","DOI":"10.1016\/S0140-6736(18)32596-0","article-title":"Epilepsy in adults","volume":"393","author":"Thijs RD","year":"2019","journal-title":"Lancet"},{"issue":"9971","key":"e_1_2_13_3_1","doi-asserted-by":"crossref","first-page":"884","DOI":"10.1016\/S0140-6736(14)60456-6","article-title":"Epilepsy: new advances","volume":"385","author":"Moshe 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