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Robins JM, VanderWeele TJ, Gill RD.Robins JM, et al. Among authors: gill rd.Scand Stat Theory Appl. 2015 Jun 1;42(2):329-335. doi: 10.1111/sjos.12089.Scand Stat Theory Appl. 2015.PMID: 26236075Free PMC article.