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Cobb CO, Foulds J, Yen MS, Veldheer S, Lopez AA, Yingst JM, Bullen C, Kang L, Eissenberg T; Randomised Control Trial Methods Workgroup of the Center for the Study of Tobacco Products.Cobb CO, et al. Among authors: foulds j.Lancet Respir Med. 2021 Aug;9(8):840-850. doi: 10.1016/S2213-2600(21)00022-9. Epub 2021 Apr 12.Lancet Respir Med. 2021.PMID: 33857436Free PMC article.Clinical Trial.