Number Needed to Treat—Just One of the Cards in the Pack

  • Andrew Moore
    Address reprint requests to Andrew Moore, DSc, Pain Research and Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurology, University of Oxford, The Churchill, Oxford OX3 7LE, United Kingdom.
    Pain Research and Nuffield Division of Anaesthetics, University of Oxford, The Churchill, Oxford, United Kingdom
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      When evaluating the efficacy of analgesics, we take into account a range of different issues. Most are obvious, but the most contentious are the linked issues of perspective, outcome, and how we explain the results to others. We have choices for each:
      • Are we using an explanatory perspective (is this drug an analgesic) or a pragmatic perspective (how well might it work in clinical practice)?
      • Are we satisfied with a 10% reduction in average pain score, or do we want to know how many patients have useful pain reduction (by 30% or 50% or more)?
      • Are we satisfied with P values, or do we want a measure of the absolute number of patients who benefit?
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      Linked Article

      • A Review of the Use of the Number Needed to Treat to Evaluate the Efficacy of Analgesics
        The Journal of PainVol. 16Issue 2
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          Standardized measures of efficacy are needed to compare analgesic efficacy across trials. The number needed to treat (NNT) is considered a statistically robust and readily interpretable measure to rank the efficacy of treatments, including analgesics. The NNT has become widely utilized to compare the efficacy of chronic pain treatments, helping physicians make treatment decisions and informing decisions for market access, reimbursement, and treatment guidelines. However, the NNT is associated with specific weaknesses in calculation and interpretation not associated with other methods for integrating trial data.
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