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Updated: Jun 23, 2026

Evidence-based Knowledge Synthesis and Hypothesis Validation: Navigating Biomedical Knowledge Bases via Explainable AI and Agentic Systems
Published on: June 13, 2025
Hierarchy of evidence: where observational studies fit in and why we need them
Daniel J Hoppe1, Emil H Schemitsch, Saam Morshed
1Division of Orthopaedic Surgery, Department of Surgery, McMaster University, 293 Wellington Street North, Suite 110, Hamilton, ON L8L 2X2, Canada.
Abstract:
Although randomized controlled designs are considered the so-called gold standard in medical trials and sit atop the hierarchy of evidence in evidence-based medicine, there are situations in which they are impractical or unethical to undertake, especially in surgical trials. Then, observational studies often provide the best source of information. In this paper, we use examples from the literature to explain the importance of observational studies in furthering the boundaries of orthopaedic surgery and knowledge of musculoskeletal disorders.
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