Calculates the Number Needed to Treat, which is the number of patients who need to receive an intervention for one patient to experience the desired outcome.
Start with your values, or try a preset.
Enter Experimental Event Rate (EER) - Proportion of patients in the experimental group experiencing the event and Control Event Rate (CER) - Proportion of patients in the control group experiencing the event in the units shown.
Read Absolute Risk Reduction (ARR) and Number Needed to Treat (NNT) in the results panel. Results update as you change the inputs.
Choose a preset to load an example, then adjust the values for your situation.
See the inputs and their calculated results.
Experimental Event Rate (EER) - Proportion of patients in the experimental group experiencing the event: 0.1; Control Event Rate (CER) - Proportion of patients in the control group experiencing the event: 0.2
Absolute Risk Reduction (ARR): 0.1; Number Needed to Treat (NNT): 10
Experimental Event Rate (EER) - Proportion of patients in the experimental group experiencing the event: 0.05; Control Event Rate (CER) - Proportion of patients in the control group experiencing the event: 0.15
Absolute Risk Reduction (ARR): 0.1; Number Needed to Treat (NNT): 10
Experimental Event Rate (EER) - Proportion of patients in the experimental group experiencing the event: 0.2; Control Event Rate (CER) - Proportion of patients in the control group experiencing the event: 0.3
Absolute Risk Reduction (ARR): 0.1; Number Needed to Treat (NNT): 10
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