Enter the control group % and the experiment group % into the NNT calculator. The calculator will display the total number of patients that need to be treated to achieve an endpoint.
Number Needed to Treat Formula
The following formula is used to calculate the total number of patients that need to be treated in order to achieve a result.
- Where NNT is the number of patients that need to be treated
- ARR is the absolute risk reduction
Further more, ARR can be calculated through the following equation.
ARR=CER – EER
- Where CER is the control event rate
- EER is the experiment event rate
Number Needed to Treat Definition
The number needed to treat is defined as the total estimate of people that need to be treated of a disease in order to mitigate transmission.
How to calculate number needed to treat?
How to calculate a number needed to treat
- First, measure the control event rate
This will be the percent treated in the control event.
- Next, measure the experiment event rate
This will be the percent treated in the experiment.
- Lastly, calculate the NNT
Using the formula above and the information from steps 1-2 to calculate the NNT
NNT stands for number needed to treat. It’s a term used in medicine to describe the total number of patients needed to be treated in order to achieve a given result.