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Elkington AR, Khaw PT.Elkington AR, et al.Br Med J (Clin Res Ed). 1988 Jun 25;296(6639):1787-90. doi: 10.1136/bmj.296.6639.1787.Br Med J (Clin Res Ed). 1988.PMID: 3136840Free PMC article.Review.No abstract available.