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Kalkdijk-Dijkstra AJ, van der Heijden JAG, van Westreenen HL, Broens PMA, Trzpis M, Pierie JPEN, Klarenbeek BR; FORCE Trial Group.Kalkdijk-Dijkstra AJ, et al.Trials. 2020 Jan 28;21(1):112. doi: 10.1186/s13063-019-4043-7.Trials. 2020.PMID: 31992358Free PMC article.