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Anderson HR, Ponce de Leon A, Bland JM, Bower JS, Strachan DP.Anderson HR, et al. Among authors: strachan dp.BMJ. 1996 Mar 16;312(7032):665-9. doi: 10.1136/bmj.312.7032.665.BMJ. 1996.PMID: 8597732Free PMC article.