{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T15:50:42Z","timestamp":1788018642172,"version":"build-2784847793"},"reference-count":23,"publisher":"Oxford University Press (OUP)","issue":"8","license":[{"start":{"date-parts":[[2019,12,17]],"date-time":"2019-12-17T00:00:00Z","timestamp":1576540800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,8,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>We estimated breast cancer (BC) mortality reduction associated with invitations to a nationwide population-based screening program and with changes in treatment.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Materials and methods<\/jats:title>\n                  <jats:p>BreastScreen Norway started in 1996 and became nationwide in 2005. It invites women aged 50\u201369 years to biennial mammographic screening. We retrieved individual-level data for 1\u00a0340\u00a0333 women from national registries. During 1996\u20132014 (screening window), women contributed person-years in noninvited and invited periods. We created comparable periods for 1977\u20131995 (prescreening window) by dividing the follow-up time for each woman into pseudo-noninvited and pseudo-invited periods. We estimated BC mortality for the four periods, using the so-called evaluation model: counting BC deaths in each period for all women diagnosed within the period and counting BC deaths and person-years after screening-age for those diagnosed within screening age. We used a multivariable flexible parametric survival model to estimate hazard ratio (HR) for the effect of invitation and improved treatment.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Using the regression approach, we found 5818 BC deaths across 16\u00a0533\u00a0281 person-years. Invitations to screening reduced BC mortality by 20% (HR = 0.80, 95% confidence interval [CI] = 0.70 to 0.91) among women 50\u2009years and older and by 25% (HR = 0.75, 95% CI = 0.65 to 0.86) among screening-aged women. The treatment effect was 23% (HR = 0.77, 95% CI = 0.65 to 0.92) for women 50\u2009years and older and 17% (HR = 0.83, 95% CI = 0.74 to 0.94) for screening-aged women.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>We observed a similar reduction in BC mortality associated with invitations to screening and improvements in treatment during 1977\u20132014, among women 50\u2009years and older.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jnci\/djz220","type":"journal-article","created":{"date-parts":[[2019,12,9]],"date-time":"2019-12-09T12:07:17Z","timestamp":1575893237000},"page":"839-846","source":"Crossref","is-referenced-by-count":27,"title":["Breast Cancer Mortality After Implementation of Organized Population-Based Breast Cancer Screening in Norway"],"prefix":"10.1093","volume":"112","author":[{"given":"Sofie","family":"Sebu\u00f8deg\u00e5rd","sequence":"first","affiliation":[{"name":"Section for Breast Cancer Screening, Cancer Registry of Norway, Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9581-1468","authenticated-orcid":false,"given":"Edoardo","family":"Botteri","sequence":"additional","affiliation":[{"name":"Section for Colorectal Cancer Screening, Cancer Registry of Norway, Oslo, Norway"},{"name":"Norwegian National Advisory Unit on Women\u2019s Health, Women\u2019s Clinic, Oslo University Hospital, Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0178-8939","authenticated-orcid":false,"given":"Solveig","family":"Hofvind","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, Oslo Metropolitan University, Oslo, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2019,12,17]]},"reference":[{"issue":"6","key":"2020081703570595200_djz220-B1","first-page":"CD001877","article-title":"Screening for breast cancer with mammography","volume":"2013","author":"Gotzsche","journal-title":"Cochrane Database Syst Rev"},{"key":"2020081703570595200_djz220-B2","volume-title":"Breast Cancer Screening IARC Handbook of Cancer Prevention","year":"2016"},{"issue":"9855","key":"2020081703570595200_djz220-B3","doi-asserted-by":"crossref","first-page":"1778","DOI":"10.1016\/S0140-6736(12)61611-0","article-title":"The benefits and harms of breast cancer screening: an independent review","volume":"380","year":"2012","journal-title":"Lancet"},{"key":"2020081703570595200_djz220-B4"},{"issue":"3","key":"2020081703570595200_djz220-B5","doi-asserted-by":"crossref","first-page":"658","DOI":"10.1148\/radiol.11110469","article-title":"Swedish two-county trial: impact 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