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Quintana FA, Johnson WO, Waetjen E, Gold E.Quintana FA, et al. Among authors: waetjen e.J Am Stat Assoc. 2016;111(515):1168-1181. doi: 10.1080/01621459.2015.1076725. Epub 2016 Oct 18.J Am Stat Assoc. 2016.PMID: 28366967Free PMC article.