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Horne AW, Critchley HO, Doust A, Fehr D, Wilson J, Wu O, Jack S, Porter M, Lewis S, Bhattacharya S.Horne AW, et al.BMJ Open. 2012 Jun 8;2(3):e001297. doi: 10.1136/bmjopen-2012-001297. Print 2012.BMJ Open. 2012.PMID: 22685224Free PMC article.