{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2022,3,31]],"date-time":"2022-03-31T00:17:49Z","timestamp":1648685869878},"reference-count":15,"publisher":"Cambridge University Press (CUP)","issue":"1","license":[{"start":{"date-parts":[[2014,11,27]],"date-time":"2014-11-27T00:00:00Z","timestamp":1417046400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Twin Res Hum Genet"],"published-print":{"date-parts":[[2015,2]]},"abstract":"<jats:p>We analyzed the effect of total fertility rate (TFR) and crude birth rate (CBR) on the number of males per 100 females at birth, also called the secondary sex ratio (SR), and on the twinning rate (TWR). Earlier studies have noted regional variations in TWR and racial differences in the SR. Statistical analyses have shown that comparisons between SRs demand large data sets because random fluctuations in moderate data are marked. Consequently, reliable results presuppose national birth data. Here, we analyzed historical demographic data and their regional variations between counties in Sweden. We built spatial models for the TFR in 1860 and the CBR in 1751\u20131870, and as regressors we used geographical coordinates for the provincial capitals of the counties. For both variables, we obtained significant spatial variations, albeit of different patterns and power. The SR among the live-born in 1749\u20131869 and the TWR in 1751\u20131860 showed slight spatial variations. The influence of CBR and TFR on the SR and TWR was examined and statistical significant effects were found.<\/jats:p>","DOI":"10.1017\/thg.2014.71","type":"journal-article","created":{"date-parts":[[2014,11,27]],"date-time":"2014-11-27T10:49:13Z","timestamp":1417085353000},"page":"92-99","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Fertility on Secondary Sex Ratio and Twinning Rate in Sweden, 1749\u20131870"],"prefix":"10.1017","volume":"18","author":[{"given":"Johan","family":"Fellman","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aldur W.","family":"Eriksson","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"56","published-online":{"date-parts":[[2014,11,27]]},"reference":[{"key":"S1832427414000711_ref010","doi-asserted-by":"publisher","DOI":"10.1007\/s00431-012-1923-1"},{"key":"S1832427414000711_ref011","doi-asserted-by":"publisher","DOI":"10.1111\/ped.12063"},{"key":"S1832427414000711_ref003","doi-asserted-by":"publisher","DOI":"10.1375\/136905203765693834"},{"key":"S1832427414000711_ref012","first-page":"361","volume-title":"The study of population: An inventory and appraisal","author":"Hawley","year":"1959"},{"key":"S1832427414000711_ref007","doi-asserted-by":"publisher","DOI":"10.1080\/19485565.2011.614193"},{"key":"S1832427414000711_ref002","unstructured":"Eriksson A. W. (1973). Human twinning in and around the \u00c5land Islands. Commentationes Biologicae, 64, 1\u2013159."},{"key":"S1832427414000711_ref006","doi-asserted-by":"publisher","DOI":"10.1375\/twin.13.1.101"},{"key":"S1832427414000711_ref001","first-page":"1","article-title":"Proportionen mellan k\u00f6nen bland de f\u00f6dde och inom den st\u00e5ende befolkningen med h\u00e4nsyn till Sverige och dess provinciela olikheter. [Sex ratio at birth and in the population with respect to Sweden and its regions]","volume":"10","author":"Berg","year":"1871","journal-title":"Kungliga Svenska Vetenskaps-Akademiens Handlingar"},{"key":"S1832427414000711_ref009","doi-asserted-by":"crossref","first-page":"761","DOI":"10.1177\/1403494812464447","article-title":"Sex ratios at birth in Scandinavia over the past sixty years","volume":"40","author":"Grech","year":"2012","journal-title":"Scandinavian Journal of Public Health"},{"key":"S1832427414000711_ref014","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/der390"},{"key":"S1832427414000711_ref015","doi-asserted-by":"publisher","DOI":"10.1080\/19485565.1967.9987713"},{"key":"S1832427414000711_ref008","doi-asserted-by":"publisher","DOI":"10.1159\/000066191"},{"key":"S1832427414000711_ref013","volume-title":"Swedish population history. Main trends from 1750 to 1970","author":"Hofsten","year":"1976"},{"key":"S1832427414000711_ref005","doi-asserted-by":"publisher","DOI":"10.1375\/twin.12.6.583"},{"key":"S1832427414000711_ref004","doi-asserted-by":"publisher","DOI":"10.1375\/twin.8.2.163"}],"container-title":["Twin Research and Human Genetics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S1832427414000711","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,4,21]],"date-time":"2019-04-21T18:56:34Z","timestamp":1555872994000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S1832427414000711\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,11,27]]},"references-count":15,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2015,2]]}},"alternative-id":["S1832427414000711"],"URL":"https:\/\/doi.org\/10.1017\/thg.2014.71","relation":{},"ISSN":["1832-4274","1839-2628"],"issn-type":[{"value":"1832-4274","type":"print"},{"value":"1839-2628","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,11,27]]}}}