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Zheng W, Balzer L, van der Laan M, Petersen M; SEARCH Collaboration.Zheng W, et al.Stat Med. 2018 Jan 30;37(2):261-279. doi: 10.1002/sim.7296. Epub 2017 Apr 6.Stat Med. 2018.PMID: 28384841Free PMC article.