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Oord M, Olgers TJ, Doff-Holman M, Harms MP, Ligtenberg JJ, Ter Maaten JC.Oord M, et al. Among authors: olgers tj.BMJ Open. 2017 Jan 27;7(1):e013465. doi: 10.1136/bmjopen-2016-013465.BMJ Open. 2017.PMID: 28132006Free PMC article.