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Strachan BK, van Wijngaarden WJ, Sahota D, Chang A, James DK.Strachan BK, et al. Among authors: chang a.Lancet. 2000 Feb 5;355(9202):456-9. doi: 10.1016/S0140-6736(00)82012-7.Lancet. 2000.PMID: 10841126Clinical Trial.