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Seng JJB, Monteiro AY, Kwan YH, Zainudin SB, Tan CS, Thumboo J, Low LL.Seng JJB, et al.BMC Med Res Methodol. 2021 Mar 11;21(1):49. doi: 10.1186/s12874-021-01209-w.BMC Med Res Methodol. 2021.PMID: 33706717Free PMC article.Review.