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Swanson SA, Hernán MA, Miller M, Robins JM, Richardson TS.Swanson SA, et al. Among authors: hernan ma.J Am Stat Assoc. 2018;113(522):933-947. doi: 10.1080/01621459.2018.1434530. Epub 2018 Jul 25.J Am Stat Assoc. 2018.PMID: 31537952Free PMC article.