Risk measures expressed as frequencies may have a more rational responseBMJ 1995; 310 doi: https://doi.org/10.1136/bmj.310.6989.1269a (Published 13 May 1995) Cite this as: BMJ 1995;310:1269
- Peter Ayton
- Lecturer in psychology Department of Psychology, School of Social Sciences, City University, London EC1V 0HB
EDITOR,—Richard J Cook and David L Sackett propose that the number needed to treat (to avoid an adverse event) should be used as a measure of the efficacy of treatment in reducing medical risks.1 This measure has advantages over probability measures (for example, reduction in relative risk) as it conveys both statistical and clinical significance.
A treatment that reduces deaths by 50% sounds better than one that reduces deaths by 5%, yet the latter treatment might be more valuable than the former: …