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Nelson A, Wright-Hughes A, Backhouse MR, Lipsky BA, Nixon J, Bhogal MS, Reynolds C, Brown S; CODIFI collaborators.Nelson A, et al.BMJ Open. 2018 Jan 31;8(1):e019437. doi: 10.1136/bmjopen-2017-019437.BMJ Open. 2018.PMID: 29391370Free PMC article.