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Middleton S, Lydtin A, Comerford D, Cadilhac DA, McElduff P, Dale S, Hill K, Longworth M, Ward J, Cheung NW, D'Este C; QASCIP Working Group and Steering Committee.Middleton S, et al.BMJ Open. 2016 May 6;6(5):e011568. doi: 10.1136/bmjopen-2016-011568.BMJ Open. 2016.PMID: 27154485Free PMC article.