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Yao Q, Wei LJ.Yao Q, et al. Among authors: wei lj.Stat Med. 1996 Nov 15-30;15(21-22):2413-23; discussion 2455-8. doi: 10.1002/(sici)1097-0258(19961130)15:22<2413::aid-sim460>3.0.co;2-n.Stat Med. 1996.PMID: 8931210
Park Y, Tian L, Wei LJ.Park Y, et al. Among authors: wei lj.Biostatistics. 2006 Apr;7(2):252-67. doi: 10.1093/biostatistics/kxj005. Epub 2005 Nov 10.Biostatistics. 2006.PMID: 16282531
Li Y, Tian L, Wei LJ.Li Y, et al. Among authors: wei lj.Biometrics. 2011 Jun;67(2):427-35. doi: 10.1111/j.1541-0420.2010.01456.x. Epub 2010 Jul 9.Biometrics. 2011.PMID: 20618311Free PMC article.