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McKendrick MW, McGill JI, White JE, Wood MJ.McKendrick MW, et al.Br Med J (Clin Res Ed). 1986 Dec 13;293(6561):1529-32. doi: 10.1136/bmj.293.6561.1529.Br Med J (Clin Res Ed). 1986.PMID: 3099943Free PMC article.Clinical Trial.