##  [Number Needed to Treat](/index.php/number-needed-treat) 

  ##  [Number Needed to Treat](https://health.quantumdictionary.io/number-needed-treat-0) 

  

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**Health & Life Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The reciprocal of the absolute risk reduction over a specified follow‑up period: NNT = 1 / ARR; it indicates the number of patients who must receive the intervention for one additional patient to experience the beneficial outcome compared with control, where NNT is meaningful only when ARR and the time frame are explicitly defined.