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Brandlistuen RE, Ystrom E, Eberhard-Gran M, Nulman I, Koren G, Nordeng H.Brandlistuen RE, et al. Among authors: nordeng h.Int J Epidemiol. 2015 Aug;44(4):1397-407. doi: 10.1093/ije/dyv030. Epub 2015 Apr 14.Int J Epidemiol. 2015.PMID: 25873178Free PMC article.