- •The NNT has become widely used to compare the efficacy of chronic pain treatments.
- •But the NNT is associated with distortions in calculation (eg, infinite values).
- •The NNT also requires selecting cutoffs, thus changing with the cutoff.
- •The NNT is also difficult to interpret, even by medical professionals.
- •Clinicians should be aware of these issues to calculate, use, and interpret the NNT.
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The authors received a grant from Janssen Pharmaceuticals to support independent writing of this review.
The authors declare having no financial relationship to the work. N.K. and R.V.I. are employees and F.C.P. is a contractor of Analgesic Solutions.