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Review
. 2004 Aug 17;171(4):353-8.
doi: 10.1503/cmaj.1021197.

Tips for learners of evidence-based medicine: 1. Relative risk reduction, absolute risk reduction and number needed to treat

Alexandra Barratt  1 , Peter C Wyer, Rose Hatala, Thomas McGinn, Antonio L Dans, Sheri Keitz, Virginia Moyer, Gordon Guyatt For; Evidence-Based Medicine Teaching Tips Working Group
Affiliations
Review

Tips for learners of evidence-based medicine: 1. Relative risk reduction, absolute risk reduction and number needed to treat

Alexandra Barratt et al. CMAJ. .
No abstract available

PubMed Disclaimer

Figures

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Fig. 1: Results of hypothetical placebo-controlled trials of a new drug for acute myocardial infarction. The bars represent the 30-day mortality rate in different groups of patients with acute myocardial infarction and heart failure. A: Trial involving patients at high risk for the adverse outcome. B: Trials involving a group of patients at high risk for the adverse outcome and another group of patients at low risk for the adverse outcome.
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See this image and copyright information in PMC

Comment in

  • Tips for learning and teaching evidence-based medicine: introduction to the series.
    Wyer PC, Keitz S, Hatala R, Hayward R, Barratt A, Montori V, Wooltorton E, Guyatt G. Wyer PC, et al. CMAJ. 2004 Aug 17;171(4):347-8. doi: 10.1503/cmaj.1031665. CMAJ. 2004. PMID: 15313994 Free PMC article. No abstract available.
  • Views on recertification.
    Vandor T. Vandor T. CMAJ. 2004 Nov 23;171(11):1321. doi: 10.1503/cmaj.1041650. CMAJ. 2004. PMID: 15557563 Free PMC article. No abstract available.
  • NNT for studies with long-term follow-up.
    de Lemos ML. de Lemos ML. CMAJ. 2005 Mar 1;172(5):613; author reply 613-5. doi: 10.1503/cmaj.1041426. CMAJ. 2005. PMID: 15738471 Free PMC article. No abstract available.
  • Challenges of teaching EBM.
    Burns GE. Burns GE. CMAJ. 2005 May 24;172(11):1423-4; author reply 1424-5. doi: 10.1503/cmaj.1041708. CMAJ. 2005. PMID: 15911841 Free PMC article. No abstract available.
  • Challenges of teaching EBM.
    Siden H. Siden H. CMAJ. 2005 May 24;172(11):1423; author reply 1424-5. doi: 10.1503/cmaj.1041600. CMAJ. 2005. PMID: 15911842 Free PMC article. No abstract available.
  • Not-so-surprising findings.
    Schneeweiss S, Solomon DH. Schneeweiss S, et al. CMAJ. 2006 Jul 18;175(2):171-2; author reply 172. doi: 10.1503/cmaj.1060090. CMAJ. 2006. PMID: 16847278 Free PMC article. No abstract available.

References

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    1. Naylor CD, Chen E, Strauss B. Measured enthusiasm: Does the method of reporting trial results alter perceptions of therapeutic effectiveness? Ann Intern Med 1992;117:916-21. - PubMed
    1. Fahey T, Griffiths S, Peters TJ. Evidence based purchasing: understanding results of clinical trials and systematic reviews. BMJ 1995;311:1056-60. - PMC - PubMed
    1. Jaeschke R, Guyatt G, Barratt A, Walter S, Cook D, McAlister F, et al. Measures of association. In: Guyatt G, Rennie D, editors. The users' guides to the medical literature: a manual of evidence-based clinical practice. Chicago: AMA Publications; 2002. p. 351-68.