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Tsonaka R, van der Helm-van Mil AH, Houwing-Duistermaat JJ.Tsonaka R, et al.Stat Med. 2012 May 20;31(11-12):1190-202. doi: 10.1002/sim.4370. Epub 2011 Oct 14.Stat Med. 2012.PMID: 21997511