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Watt AH, Routledge PA.Watt AH, et al. Among authors: routledge pa.Br Med J (Clin Res Ed). 1986 Dec 6;293(6560):1455-6. doi: 10.1136/bmj.293.6560.1455.Br Med J (Clin Res Ed). 1986.PMID: 3099909Free PMC article.No abstract available.