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GRADE guidelines: 9. Rating up the quality of evidence
Journal of Clinical Epidemiology
  • Gordon H. Guyatt, McMaster University
  • Andrew D. Oxman, Norwegian Knowledge Centre for the Health Services
  • Shahnaz Sultan, University of Florida
  • Paul P. Glasziou, Bond University
  • Elie A. Akl, State University of New York at Buffalo
  • Pablo Alonso-Coello, Universidad Autonoma de Barcelona
  • David Atkins, Department of Veterans Affairs Washington DC
  • Regina Kunz, University Hospital Basel
  • Jan Brozek, McMaster University
  • Victor Montori, Mayo Clinic
  • Roman Jaeschke, McMaster University
  • David Rind, Harvard Medical School
  • Philipp Dahm, University of Florida
  • Joerg Meerpohl, University Medical Center Freiburg
  • Gunn Vist, Norwegian Knowledge Centre for the Health Services
  • Elise Berliner, Agency for Healthcare Research and Quality
  • Susan Norris, Oregon Health & Science University
  • Yngve Falck-Ytter, Case Western Reserve University
  • M. Hassan Murad, Mayo Clinic
  • Holger J. Schunemann, McMaster University
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Journal Article
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Citation only

Guyatt, G. H., Oxman, A. D., Sultan, S., Glasziou, P. P., et al. (2011). GRADE guidelines: 9. Rating up the quality of evidence. Journal of clinical epidemiology, 64 (12), 1311-1316.

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2011 HERDC submission. FoR code: 111700

© Copyright Elsevier Inc., 2011. All rights reserved.

The most common reason for rating up the quality of evidence is a large effect. GRADE suggests considering rating up quality of evidence one level when methodologically rigorous observational studies show at least a two-fold reduction or increase in risk, and rating up two levels for at least a five-fold reduction or increase in risk. Systematic review authors and guideline developers may also consider rating up quality of evidence when a dose-response gradient is present, and when all plausible confounders or biases would decrease an apparent treatment effect, or would create a spurious effect when results suggest no effect. Other considerations include the rapidity of the response, the underlying trajectory of the condition, and indirect evidence.
Citation Information
Gordon H. Guyatt, Andrew D. Oxman, Shahnaz Sultan, Paul P. Glasziou, et al.. "GRADE guidelines: 9. Rating up the quality of evidence" Journal of Clinical Epidemiology Vol. 64 Iss. 12 (2011) p. 1311 - 1316 ISSN: 0895-4356
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