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The Evidence-based Medicine Paradigm: Where are We 20 Years Later? Part 2

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

In Part 2, we discuss the challenges of keeping up with the ‘literature,’ evidence-based medicine (EBM) in emerging economies and the Neurosciences, and two recent approaches to classifying evidence. We conclude by summarizing information from Parts 1 and 2 which suggest the need to critically re-appraise core elements of the EBM paradigm: (1) the hierarchical ranking of evidence, (2) randomized controlled trials or systematic reviews as the gold standard for all clinical questions or situations, (3) the statistical tests that have become integral to the ‘measurements’ for analyzing evidence, and (4) re-incorporating a role for evidence from basic sciences and pathophysiology. An understanding of how cognitive processes influence clinical decisions is also necessary to improve evidence-based practice. Emerging economies may have to modify the design and conduct of clinical research to their settings. Like all paradigms, EBM must keep improving with input from the grassroots to remain beneficial.


Dans cette deuxième partie, nous discutons des défis que présentent le suivi de la littérature, la médecine fondée sur des données probantes (MFDP) dans les économies émergentes et les neurosciences ainsi que deux approches novatrices de classification des données. Nous concluons par un sommaire de l'information contenue dans les parties 1 et 2 qui suggère que nous devons réévaluer de façon critique des éléments fondamentaux du paradigme de la MFDP: 1) le classement hiérarchique des données; 2) les études randomisées contrôlées ou les revues systématiques comme étalon or en ce qui concerne toutes les questions ou situations cliniques; 3) les tests statistiques qui sont devenus une partie fondamentale des « mesures » utilisées pour analyser les données et 4) le rôle des données des sciences de base et de la physiopathologie qui devrait être rétabli. La compréhension de la façon dont les processus cognitifs influencent les décisions cliniques est également nécessaire pour améliorer la pratique médicale fondée sur des preuves. Les économies émergentes pourraient devoir modifier la conception et la réalisation de la recherche clinique dans leur contexte. Comme tout paradigme, la MFDP doit s'améliorer constamment en tenant compte des contributions du milieu pour demeurer bénéfique.

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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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