Number Needed to Treat
NNT定義
The number of patients who need to be treated with a drug for one additional patient to benefit compared to a control treatment. A lower NNT indicates a more effective treatment. NNT is calculated as 1 divided by the absolute risk reduction.
例
Statins for primary cardiovascular prevention have an NNT of about 50-100 over 5 years — meaning 50-100 people need to take statins for 5 years to prevent one cardiovascular event.