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Al-Taiar A, Rahman A, Al-Sabah R, Shaban L, Al-Harbi A.Al-Taiar A, et al.BMJ Open. 2018 Aug 1;8(7):e021401. doi: 10.1136/bmjopen-2017-021401.BMJ Open. 2018.PMID: 30068613Free PMC article.