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The Evidence-based Medicine Paradigm: Where are We 20 Years Later? Part 1

  • Shashi S. Seshia (a1) and G. Bryan Young (a2)

The evidence-based medicine (EBM) paradigm, introduced in 1992, has had a major and positive impact on all aspects of health care. However, widespread use has also uncovered some limitations; these are discussed from the perspectives of two clinicians in this, the first of a two part narrative review. For example, there are credible reservations about the validity of hierarchical levels of evidence, a core element of the EBM paradigm. In addition, potential and actual methodological and statistical deficiencies have been identified, not only in many published randomized controlled trials but also in systematic reviews, both rated highly for evidence in EBM classifications. Ethical violations compromise reliability of some data. Clinicians need to be conscious of potential limitations in some of the cornerstones of the EBM paradigm, and to deficiencies in the literature.


Le paradigme de la médecine fondée sur des données probantes (MFDP) introduit en 1992 a eu un impact positif majeur sur tous les aspects des soins de santé. Cependant, son utilisation répandue a également mis au jour certaines limites. Nous discutons de ces limites du point de vue de deux cliniciens dans la première partie de cet examen narratif. Il existe, par exemple, des réserves crédibles concernant la validité des niveaux hiérarchiques de preuves, un élément clé du paradigme de la MFDP. De plus, des lacunes potentielles et réelles dans la méthodologie et l'analyse statistique ont été identifiées, non seulement dans plusieurs essais cliniques randomisés qui ont été publiés, mais également dans les revues systématiques, deux sources de données très prisées pour établir les classifications dans la MFDP. Les manquements à l'éthique compromettent la fiabilité de certaines données. Les cliniciens doivent être conscients des limites potentielles présentes dans certains principes de base du paradigme de la MFDP et des lacunes présentes dans la littérature.

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Corresponding author
Department of Pediatrics, Division of Pediatric Neurology, University of Saskatchewan, Royal University Hospital, 108 Hospital Drive, Saskatoon, Saskatchewan, S7N 0W8, Canada. Email:
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