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Joffe M, Chapple J, Paterson C, Beard RW.Joffe M, et al. Among authors: beard rw.J Epidemiol Community Health. 1994 Aug;48(4):406-11. doi: 10.1136/jech.48.4.406.J Epidemiol Community Health. 1994.PMID: 7964342Free PMC article.