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Occupational class variables included working status, occupation, employment status, and company size (number of employees). Covariates included age, socio-economic status, lifestyle, and comorbidities. Poisson regression models stratified by gender were used to estimate adjusted prevalence ratio (APR) and 95% confidence interval (CI) for self-reported LBP.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>The prevalence of self-reported LBP was 11.7% in men and 14.2% in women. After adjustment for covariates and mutual adjustment for all occupational class variables, among both genders, agricultural\/forestry\/fishery workers and non-workers had a significantly higher prevalence of self-reported LBP: APR (95% CI) of agricultural\/forestry\/fishery was 1.36 (1.08\u20131.70) in men and 1.59 (1.30\u20131.93) in women; that of non-workers was 1.42 (1.18\u20131.70) in men and 1.23 (1.08\u20131.40) in women. Among men, non-regular employees were more likely to have self-reported LBP than regular employees: APR (95% CI) was 1.25 (1.07\u20131.46) in part-timers and casual staff and 1.18 (1.03\u20131.35) in other types of non-regular employees. Moreover, compared to men working at companies with \u2265\u2009100 employees, men working at companies with 30\u201399 employees had a significantly higher prevalence of self-reported LBP (APR 1.17; 95% CI, 1.03\u20131.34). Among women, professionals and technicians (1.26; 1.11\u20131.43) and sales workers (1.22; 1.04\u20131.43) had a significantly higher prevalence of self-reported LBP than clerks. Neither employment status nor company size was associated with self-reported LBP in women. After stratified analyses by age group, similar patterns were observed in participants aged 20\u201364, but not in those aged \u2265\u200965.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>Our results suggest that self-reported LBP is highly prevalent among agricultural\/forestry\/fishery workers and the unemployed, regardless of gender, and that there are also gender differences in the association of occupational class factors with self-reported LBP. It is necessary, therefore, to take preventive measures against LBP based on gender and occupational class factors in Japan.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12199-021-01031-2","type":"journal-article","created":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T11:02:49Z","timestamp":1637319769000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Occupational status and self-reported low back pain by gender: a nation-wide cross-sectional study among the general population in Japan"],"prefix":"10.1186","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9471-6987","authenticated-orcid":false,"given":"Kimiko","family":"Tomioka","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Midori","family":"Shima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keigo","family":"Saeki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,11,19]]},"reference":[{"key":"1031_CR1","doi-asserted-by":"publisher","first-page":"1211","DOI":"10.1016\/S0140-6736(17)32154-2","volume":"390","author":"T Vos","year":"2017","unstructured":"Vos T, Abajobir AA, Abate KH, et al. 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The data provided had personally identifiable information removed. Consent to participate is not applicable for studies using existing data.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"K.S. received research grants from YKK AP Inc.; Ushio Inc.; Tokyo Electric Power Company; En-viroLife Research Institute Co., Ltd.; Sekisui Chemical Co., Ltd.; LIXIL Corp.; and KYOCERA Corp. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. The other authors declare no conflicts of interest.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"111"}}