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Shepherd BE, Liu Q, Mercaldo N, Jenkins CA, Lau B, Cole SR, Saag MS, Sterling TR.Shepherd BE, et al. Among authors: cole sr.Stat Med. 2016 Oct 30;35(24):4335-4351. doi: 10.1002/sim.7007. Epub 2016 Jun 6.Stat Med. 2016.PMID: 27264354Free PMC article.