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Ziaeian B, Xu H, Matsouaka RA, Xian Y, Khan Y, Schwamm LS, Smith EE, Fonarow GC.Ziaeian B, et al.BMC Med Res Methodol. 2021 Feb 4;21(1):23. doi: 10.1186/s12874-021-01214-z.BMC Med Res Methodol. 2021.PMID: 33541273Free PMC article.