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Chen JL, Weiss S, Heyman MB, Lustig RH.Chen JL, et al.J Public Health (Oxf). 2010 Jun;32(2):219-29. doi: 10.1093/pubmed/fdp105. Epub 2009 Nov 15.J Public Health (Oxf). 2010.PMID: 19933120Free PMC article.Clinical Trial.