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Strength of evidence and handling uncertainty: practical considerations and general observations

Published:September 02, 2011DOI:https://doi.org/10.1016/j.jclinepi.2010.11.024
      It is an interesting conundrum that while the objective of undertaking any research should be to inform clinical practice in some manner, that we should then have so much difficulty in weighing the results of such research and deciding how far it should, or should not, guide practice. The principles of evidence-based medicine (EBM) are now irrevocably imbedded in many health care systems throughout the world. Sackett et al. [
      • Sackett D.L.
      • Rosenberg M.C.
      • Gray J.A.
      • Haynes R.B.
      • Richardson W.S.
      Evidence based medicine: what it is and what it isn’t.
      ] in a much-quoted article outlined what EBM “is,” and in recognizing the practicalities involved of using such an approach, perhaps just as importantly outlined what it “isn’t.” However, even with a cursory knowledge of EBM, it soon becomes apparent that in trying to apply evidence generated from studies to clinical situations we are not dealing with certainties, rather, with varying degrees of uncertainty. In many situations, information is incomplete and decision makers must wrestle with an irreducible core of uncertainty. How we take account of and express that uncertainty within the specific context of care is the crux of the issue.
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