{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T18:02:29Z","timestamp":1790877749422,"version":"4.1.0"},"reference-count":33,"publisher":"BMJ","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["Tob Control"],"accepted":{"date-parts":[[2026,9,22]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Women in South Korea tend to underreport their smoking status due to negative social perceptions of smoking among women. This study aims to examine the differences between self-reported and cotinine-verified smoking prevalence among Korean men and women from 2008 through 2021 and to assess whether these differences have changed substantially over time.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This study was conducted using nationally representative cross-sectional data from the Korean National Health and Nutrition Examination Survey from 2008 to 2021. A total of 53\u2009696 participants were included in the analysis. Smoking prevalence based on self-report and cotinine verification was compared by year, age, household income, educational attainment and marital status. All analyses were performed separately by sex, with a urinary cotinine cut-off of 50\u2009ng\/mL.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The absolute differences in the prevalence of self-reported non-smoking among individuals with cotinine-verified smoking decreased from 5.41% in men and 8% in women in 2008 to 1.83% in men and 2.44% in women in 2021. The relative differences also declined, from 11.99% to 8.35% in men and from 57.38% to 36.42% in women. Among women, the decrease was particularly pronounced in those aged 19\u201339 years.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This study found that underreporting among women who smoke in South Korea has markedly decreased. However, approximately one-third of women who smoke continue to underreport their smoking status. Appropriate approaches are necessary for populations that tend to underreport their smoking status.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/tc-2026-060294","type":"journal-article","created":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T17:24:56Z","timestamp":1790875496000},"page":"tc-2026-060294","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Trends in hidden smoking among women in South Korea, 2008\u20132021: a comparison of self-reported and cotinine-verified smoking prevalence"],"prefix":"10.1136","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3125-7805","authenticated-orcid":false,"given":"Jung Ah","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Family Medicine, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Korea (the Republic of)"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong-Jun","family":"Cho","sequence":"additional","affiliation":[{"name":"Research Institute for Medical Sciences, Inha University Research and Business Foundation, Incheon, Korea (the Republic of)"},{"name":"University of Ulsan College of Medicine, Ulsan, Korea (the Republic of)"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min Kyung","family":"Lim","sequence":"additional","affiliation":[{"name":"Department of Social and Preventive Medicine, Inha University College of Medicine, Incheon, Korea (the Republic of)"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ichiro","family":"Kawachi","sequence":"additional","affiliation":[{"name":"Department of Social and Behavioral Sciences, Harvard T H Chan School of Public Health, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,10,1]]},"reference":[{"key":"2026100110201137000_tc-2026-060294v1.1","doi-asserted-by":"crossref","first-page":"1966","DOI":"10.1016\/j.socscimed.2010.02.025","article-title":"Factors influencing gender differences in smoking and their separate contributions: Evidence from South Korea","volume":"70","author":"Chung","year":"2010","journal-title":"Social Science & Medicine"},{"key":"2026100110201137000_tc-2026-060294v1.2","doi-asserted-by":"crossref","DOI":"10.1186\/s12939-019-1051-x","article-title":"Long-term trends in smoking prevalence and its socioeconomic inequalities in Korea, 1992-2016","volume":"18","author":"Chang","year":"2019","journal-title":"Int J Equity Health"},{"key":"2026100110201137000_tc-2026-060294v1.3","unstructured":"Korea Disease Control and Prevention Agency . 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