Welcome to the UBC Clinical Significance Calculator

Instructions: Input the data in the fields below as decimals, e.g. 0.3, for the event rates and as integers, e.g. 320, for the numbers of patients. Then hit calculate. If you make an error, hit reset.

 Rate of events in the experimental arm:


Number of patients in the experimental arm:


  Rate of events in the control arm:


 Number of patients in the control arm:


Output Fields



 Lower 95% confidence boundary

Upper 95% confidence boundary

  Absolute Risk Reduction (ARR):


 Relative Risk Reduction (RRR%):


Odds Ratio:


Number Needed to Treat (NNT):