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Chung CH, Lai CH, Chu CM, Pai L, Kao S, Chien WC.Chung CH, et al. Among authors: chien wc.BMC Public Health. 2012 Sep 6;12:744. doi: 10.1186/1471-2458-12-744.BMC Public Health. 2012.PMID: 22950416Free PMC article.