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Chopra M, Munro S, Lavis JN, Vist G, Bennett S.Chopra M, et al. Among authors: lavis jn.Lancet. 2008 Feb 23;371(9613):668-674. doi: 10.1016/S0140-6736(08)60305-0.Lancet. 2008.PMID: 18295024