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Anim-Somuah M, Smyth RM, Jones L.Anim-Somuah M, et al. Among authors: smyth rm.Cochrane Database Syst Rev. 2011 Dec 7;(12):CD000331. doi: 10.1002/14651858.CD000331.pub3.Cochrane Database Syst Rev. 2011.PMID: 22161362Updated.Review.