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Li Y, Lee Y, Wolfe RA, Morgenstern H, Zhang J, Port FK, Robinson BM.Li Y, et al. Among authors: wolfe ra.Stat Med. 2015 Mar 30;34(7):1150-68. doi: 10.1002/sim.6404. Epub 2014 Dec 29.Stat Med. 2015.PMID: 25546152Free article.