{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:27:53Z","timestamp":1792787273470,"version":"4.5.0"},"reference-count":31,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"unspecified","delay-in-days":14,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"KDCA (Korea Disease Control and Prevention Agency), formerly Korea Centers for Disease Control and Prevention","award":["No.00228179100"],"award-info":[{"award-number":["No.00228179100"]}],"id":[{"id":"https:\/\/ror.org\/04jgeq066","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,6,28]]},"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To assess variations in compliance with SARS-CoV-2 diagnostic testing by examining the prevalence of unreported infections according to socioeconomic factors including occupation and employment type. We hypothesised that individuals in more precarious employment conditions would be less likely to undergo COVID-19 testing.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Nationwide follow-up survey linked to a prior seroprevalence study (K-SEROSMART).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>General population-based study conducted across 258 counties in South Korea.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>The final analysis included 4502 individuals aged 19 years and older who completed both the socioeconomic survey and SARS-CoV-2 antibody testing and were reactive for anti-nucleocapsid (N) antibodies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary outcome measures<\/jats:title>\n                    <jats:p>The primary outcome was non-compliance with COVID-19 diagnostic testing, defined as the absence of a self-reported confirmed diagnosis among individuals who tested reactive for anti-SARS-CoV-2 nucleocapsid (N) antibodies, indicating a history of natural infection.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Non-compliance with diagnostic testing was significantly associated with socioeconomic characteristics. Self-employed individuals (adjusted OR (aOR) 1.97, 95%\u2009CI 1.47 to 2.65)\u2009and non-regular workers (aOR 1.45, 95%\u2009CI 1.09 to 1.93) had higher odds of unreported infection compared with regular workers. In the analysis by occupational group, certain occupations showed significant associations in the univariate analysis; however, these associations did not retain statistical significance in the multivariable analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Socioeconomic disparities play an important role in compliance with COVID-19 diagnostic testing. Individuals in precarious employment may face barriers to testing, contributing to undetected infections. Policies that improve access to testing and reduce employment-related constraints, such as paid sick leave, may help mitigate these disparities. Future research should investigate the specific reasons underlying non-compliance with testing and assess its contribution to community transmission.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-100066","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T14:00:46Z","timestamp":1789480846000},"page":"e100066","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Employment type and non-compliance with SARS-CoV-2 diagnostic testing: insights from a nationwide seroprevalence study in South Korea"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0379-2237","authenticated-orcid":false,"given":"Youngook","family":"Jang","sequence":"first","affiliation":[{"name":"North America and Europe Team, Korea Institute for International Economic Policy, Sejong, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7017-1145","authenticated-orcid":false,"given":"Kyuhyun","family":"Yoon","sequence":"additional","affiliation":[{"name":"Institute of Health and Environment, Seoul National University, Gwanak-gu, Seoul, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7790-0160","authenticated-orcid":false,"given":"Suyoung","family":"Jo","sequence":"additional","affiliation":[{"name":"Institute of Health and Environment, Seoul National University, Gwanak-gu, Seoul, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4649-0012","authenticated-orcid":false,"given":"Jina","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Occupational and Environmental Medicine, Ajou University School of Medicine, Suwon-si, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7715-5372","authenticated-orcid":false,"given":"Jung Ae","family":"Kim","sequence":"additional","affiliation":[{"name":"College of Nursing, Kyungbok University, Pocheon-si, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8900-5542","authenticated-orcid":false,"given":"Hye Jin","family":"Baek","sequence":"additional","affiliation":[{"name":"Department of Occupational and Environmental Medicine, Ajou University School of Medicine, Suwon-si, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4856-3668","authenticated-orcid":false,"given":"Jaehun","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Preventive Medicine, Korea University College of Medicine, Seongbuk-gu, Seoul, Republic of Korea"},{"name":"Institute for Future 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