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Murphy MH, Murtagh EM, Boreham CA, Hare LG, Nevill AM.Murphy MH, et al. Among authors: murtagh em.BMC Public Health. 2006 May 22;6:136. doi: 10.1186/1471-2458-6-136.BMC Public Health. 2006.PMID: 16716211Free PMC article.Clinical Trial.