{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T01:45:01Z","timestamp":1777859101478,"version":"3.51.4"},"reference-count":21,"publisher":"SAGE Publications","issue":"2","license":[{"start":{"date-parts":[[2016,10,31]],"date-time":"2016-10-31T00:00:00Z","timestamp":1477872000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["J Prim Care Community Health"],"published-print":{"date-parts":[[2017,4]]},"abstract":"<jats:p>Purpose: Half of US states mandate women be notified if they have dense breasts on their mammogram, yet guidelines and data on supplemental screening modalities are limited. Breast density (BD) refers to the extent that breast tissue appears radiographically dense on mammograms. High BD reduces the sensitivity of screening mammography and increases breast cancer risk. The aim of this study was to determine the potential impact of California\u2019s 2013 BD notification legislation on breast cancer screening patterns. Methods: We conducted a cohort study of women aged 40 to 74 years who were members of a large Northern California integrated health plan (approximately 3.9 million members) in 2011-2015. We calculated pre- and post-legislation rates of screening mammography and magnetic resonance imaging (MRI). We also examined whether women with dense breasts (defined as BI-RADS density c or d) had higher MRI rates than women with nondense breasts (defined as BI-RADS density a or b). Results: After adjustment for race\/ethnicity, age, body mass index, medical facility, neighborhood median income, and cancer history, there was a relative 6.6% decrease (relative risk [RR] 0.934, confidence interval [CI] 0.92-0.95) in the rate of screening mammography, largely driven by a decrease among women &lt;50 years. While infrequent, there was a relative 16% increase (RR 1.16, CI 1.07-1.25) in the rate of screening MRI, with the greatest increase among the youngest women. In the postlegislation period, women with extremely dense breasts (BI-RADS d) had 2.77 times (CI 1.93-3.95) the odds of a MRI within 9 months of a screening mammogram compared with women with nondense breasts (BI-RADS b). Conclusions: In this setting, MRI rates increased in the postlegislation period. In addition, women with higher BD were more likely to have supplementary MRI. The decrease in mammography rates seen primarily among younger women may have been due to changes in national screening guidelines.<\/jats:p>","DOI":"10.1177\/2150131916674889","type":"journal-article","created":{"date-parts":[[2016,10,31]],"date-time":"2016-10-31T20:29:50Z","timestamp":1477945790000},"page":"55-62","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":17,"title":["The Effect of California\u2019s Breast Density Notification Legislation on Breast Cancer Screening"],"prefix":"10.1177","volume":"8","author":[{"given":"Stephanie Lynn","family":"Chau","sequence":"first","affiliation":[{"name":"Kaiser Permanente Oakland Medical Center, Oakland, CA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amy","family":"Alabaster","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Northern California, Oakland, CA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Karin","family":"Luikart","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Northern California, Oakland, CA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leslie Manace","family":"Brenman","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Northern California, Oakland, CA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laurel A.","family":"Habel","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Northern California, Oakland, CA, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2016,10,31]]},"reference":[{"key":"bibr1-2150131916674889","unstructured":"American Cancer Society. What are the key statistics about breast cancer? http:\/\/www.cancer.org\/cancer\/breastcancer\/detailedguide\/breast-cancer-key-statistics. Updated 2015. Accessed December 2, 2015."},{"key":"bibr2-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1148\/rg.352140106."},{"key":"bibr3-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1016\/j.maturitas.2012.08.004."},{"key":"bibr4-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.2014.57.0325."},{"key":"bibr5-2150131916674889","doi-asserted-by":"publisher","DOI":"10.2214\/AJR.14.13558."},{"key":"bibr6-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.13131217."},{"key":"bibr7-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1007\/s10549-015-3534-9."},{"key":"bibr8-2150131916674889","doi-asserted-by":"publisher","DOI":"10.7326\/M14-1465."},{"key":"bibr9-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1016\/j.mayocp.2013.12.014."},{"key":"bibr10-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1001\/jamainternmed.2015.3040."},{"key":"bibr11-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1093\/jnci\/dju255."},{"key":"bibr12-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacr.2015.04.015."},{"key":"bibr13-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1080\/08998280.2015.11929171"},{"key":"bibr14-2150131916674889","unstructured":"Breast cancer screening. NCQA Report Cards Web site. http:\/\/www.ncqa.org\/report-cards\/health-plans\/state-of-health-care-quality\/2015-table-of-contents\/breast-cancer. Updated 2015. Accessed June 21, 2016."},{"key":"bibr15-2150131916674889","doi-asserted-by":"publisher","DOI":"10.7326\/M15-1789."},{"key":"bibr16-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1097\/gme.0b013e318032569c."},{"key":"bibr17-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacr.2014.09.042."},{"key":"bibr18-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1148\/rg.352140134."},{"key":"bibr19-2150131916674889","unstructured":"U.S. Preventive Services Task Force. Breast cancer: screening. November 2009. http:\/\/www.uspreventiveservicestaskforce.org\/Page\/Document\/UpdateSummaryFinal\/breast-cancer-screening. Updated 2016. Accessed April 13, 2016."},{"key":"bibr20-2150131916674889","author":"National Comprehensive Cancer Network","year":"2015","journal-title":"NCCN Clinical Practice Guidelines in Oncology"},{"key":"bibr21-2150131916674889","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacr.2014.10.027."}],"container-title":["Journal of Primary Care &amp; Community Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/2150131916674889","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1177\/2150131916674889","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/2150131916674889","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T00:24:52Z","timestamp":1777508692000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/2150131916674889"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,10,31]]},"references-count":21,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2017,4]]}},"alternative-id":["10.1177\/2150131916674889"],"URL":"https:\/\/doi.org\/10.1177\/2150131916674889","relation":{},"ISSN":["2150-1319","2150-1327"],"issn-type":[{"value":"2150-1319","type":"print"},{"value":"2150-1327","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,10,31]]}}}