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Shahab L, Goniewicz ML, Blount BC, Brown J, McNeill A, Alwis KU, Feng J, Wang L, West R.Shahab L, et al.Ann Intern Med. 2017 Mar 21;166(6):390-400. doi: 10.7326/M16-1107. Epub 2017 Feb 7.Ann Intern Med. 2017.PMID: 28166548Free PMC article.