title: Research data closer to expectation than compatible with random sampling.
authors.forename: Ton J
authors.initials: TJ
authors.lastname: Cleophas
mesh_terms: D003625:Data Collection / Q000592:standards*; D006801:Humans; D011642:Publications / Q000592:standards*; D016032:Randomized Controlled Trials as Topic; D015983:Selection Bias