{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T20:31:37Z","timestamp":1793305897014,"version":"4.5.0"},"reference-count":28,"publisher":"Cambridge University Press (CUP)","issue":"4","license":[{"start":{"date-parts":[[2014,8,1]],"date-time":"2014-08-01T00:00:00Z","timestamp":1406851200000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Psychol. Med."],"published-print":{"date-parts":[[2015,3]]},"abstract":"<jats:sec id=\"S0033291714001780_sec_a1\"><jats:title>Background<\/jats:title><jats:p>The selection hypothesis posits that the increased rates of psychosis observed among migrants are due to selective migration of people who are predisposed to develop the disorder. To test this hypothesis, we examined whether risk factors for psychosis are more prevalent among future emigrants.<\/jats:p><\/jats:sec><jats:sec id=\"S0033291714001780_sec_a2\" sec-type=\"methods\"><jats:title>Method<\/jats:title><jats:p>A cohort of 49\u00a0321 Swedish military conscripts was assessed at age 18 years on cannabis use, IQ, psychiatric diagnosis, social adjustment, history of trauma and urbanicity of place of upbringing. Through data linkage we examined whether these exposures predicted emigration out of Sweden. We also calculated the emigrants' hypothetical relative risk compared with non-emigrants for developing a non-affective psychotic disorder.<\/jats:p><\/jats:sec><jats:sec id=\"S0033291714001780_sec_a3\" sec-type=\"results\"><jats:title>Results<\/jats:title><jats:p>Low IQ [odds ratio (OR) 0.5, 95% confidence interval (95% CI) 0.3\u20130.9] and \u2018poor social adjustment\u2019 (OR 0.4, 95% CI 0.2\u20130.8) were significantly less prevalent among prospective emigrants, whereas a history of urban upbringing (OR 2.3, 95% CI 1.4\u20133.7) was significantly more common. Apart from a non-significant increase in cannabis use among emigrants (OR 1.6, 95% CI 0.8\u20133.1), there were no major group differences in any other risk factors. Compared to non-emigrants, hypothetical relative risks for developing non-affective psychotic disorder were 0.7 (95% CI 0.4\u20131.2) and 0.8 (95% CI 0.7\u20131.0), respectively, for emigrants narrowly and broadly defined.<\/jats:p><\/jats:sec><jats:sec id=\"S0033291714001780_sec_a4\" sec-type=\"conclusion\"><jats:title>Conclusions<\/jats:title><jats:p>This study adds to an increasing body of evidence opposing the selection hypothesis.<\/jats:p><\/jats:sec>","DOI":"10.1017\/s0033291714001780","type":"journal-article","created":{"date-parts":[[2014,8,1]],"date-time":"2014-08-01T14:12:40Z","timestamp":1406902360000},"page":"727-734","source":"Crossref","is-referenced-by-count":31,"title":["Testing \u00d8degaard's selective migration hypothesis: a longitudinal cohort study of risk factors for non-affective psychotic disorders among prospective emigrants"],"prefix":"10.1017","volume":"45","author":[{"given":"E.","family":"van der Ven","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"Dalman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S.","family":"Wicks","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P.","family":"Allebeck","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"Magnusson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"van Os","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. P.","family":"Selten","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2014,8,1]]},"reference":[{"key":"S0033291714001780_ref5","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.182.2.117"},{"key":"S0033291714001780_ref28","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.bp.109.070904"},{"key":"S0033291714001780_ref20","doi-asserted-by":"publisher","DOI":"10.1080\/00332747.1974.11023818"},{"key":"S0033291714001780_ref12","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.177.5.416"},{"key":"S0033291714001780_ref14","doi-asserted-by":"publisher","DOI":"10.1186\/1471-2458-11-450"},{"key":"S0033291714001780_ref25","doi-asserted-by":"publisher","DOI":"10.1038\/nature09563"},{"key":"S0033291714001780_ref23","volume-title":"Historic Population Register","year":"2006"},{"key":"S0033291714001780_ref22","doi-asserted-by":"publisher","DOI":"10.1176\/appi.ajp.159.4.669"},{"key":"S0033291714001780_ref26","volume-title":"Manual of the International Statistical Classification of Diseases, Injuries and Causes of Death, 1965 Revision","year":"1967"},{"key":"S0033291714001780_ref8","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291797005680"},{"key":"S0033291714001780_ref2","doi-asserted-by":"publisher","DOI":"10.1007\/s00127-003-0596-5"},{"key":"S0033291714001780_ref9","doi-asserted-by":"publisher","DOI":"10.1080\/08039480500360906"},{"key":"S0033291714001780_ref7","doi-asserted-by":"publisher","DOI":"10.1007\/s00127-002-0582-3"},{"key":"S0033291714001780_ref21","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-0447.2011.01747.x"},{"key":"S0033291714001780_ref13","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(09)60072-6"},{"key":"S0033291714001780_ref17","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-0447.1962.tb01783.x"},{"key":"S0033291714001780_ref16","doi-asserted-by":"publisher","DOI":"10.1192\/bjp.172.4.308"},{"key":"S0033291714001780_ref15","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291706009494"},{"key":"S0033291714001780_ref11","doi-asserted-by":"publisher","DOI":"10.1016\/0140-6736(92)93213-7"},{"key":"S0033291714001780_ref19","doi-asserted-by":"publisher","DOI":"10.1016\/j.schres.2011.01.013"},{"key":"S0033291714001780_ref18","first-page":"1","article-title":"Emigration and insanity","volume":"4","author":"\u00d8degaard","year":"1932","journal-title":"Acta Psychiatrica Neurologica Scandinavica"},{"key":"S0033291714001780_ref3","doi-asserted-by":"publisher","DOI":"10.1017\/S0033291710001406"},{"key":"S0033291714001780_ref4","doi-asserted-by":"publisher","DOI":"10.1093\/oxfordjournals.schbul.a033460"},{"key":"S0033291714001780_ref1","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(87)92620-1"},{"key":"S0033291714001780_ref10","first-page":"229","article-title":"Validity of the diagnosis schizophrenia in a psychiatric inpatient register: a retrospective application of DSM-III criteria on ICD-8 diagnoses in Stockholm county","volume":"41","author":"Kristjansson","year":"1987","journal-title":"Nordic Journal of Psychiatry"},{"key":"S0033291714001780_ref6","doi-asserted-by":"publisher","DOI":"10.1176\/appi.ajp.162.1.12"},{"key":"S0033291714001780_ref24","volume-title":"Multi-generation Register 2009: a Description of Contents and Quality","year":"2010"},{"key":"S0033291714001780_ref27","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.325.7374.1199"}],"container-title":["Psychological Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0033291714001780","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,6,14]],"date-time":"2023-06-14T08:41:33Z","timestamp":1686732093000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0033291714001780\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,8,1]]},"references-count":28,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2015,3]]}},"alternative-id":["S0033291714001780"],"URL":"https:\/\/doi.org\/10.1017\/s0033291714001780","relation":{},"ISSN":["0033-2917","1469-8978"],"issn-type":[{"value":"0033-2917","type":"print"},{"value":"1469-8978","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,8,1]]}}}