title: Observational versus experimental studies: what's the evidence for a hierarchy?
abstract: The tenets of evidence-based medicine include an emphasis on hierarchies of research design (i.e., study architecture). Often, a single randomized, controlled trial is considered to provide "truth," whereas results from any observational study are viewed with suspicion. This paper describes information that contradicts and discourages such a rigid approach to evaluating the quality of research design. Unless a more balanced strategy evolves, new claims of methodological authority may be just as problematic as the traditional claims of medical authority that have been criticized by proponents of evidence-based medicine.
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06510, USA. john.concato@yale.edu
authors.forename: John
authors.initials: J
authors.lastname: Concato
mesh_terms: D016022:Case-Control Studies; D002986:Clinical Trials as Topic / Q000379:methods*; D015331:Cohort Studies; D019317:Evidence-Based Medicine; D006801:Humans; D019370:Observation / Q000379:methods; D016032:Randomized Controlled Trials as Topic; D012107:Research Design
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