NNT
Also written as: NNT — Number Needed to Treat
Number needed to treat; indicates how many patients must receive an intervention to prevent one adverse outcome.
Full Definition
Number needed to treat (NNT) is a key epidemiological measure that quantifies treatment effectiveness by indicating how many patients must receive a specific intervention to prevent one additional adverse event compared to control treatment. In cardiovascular prevention, NNT helps clinicians and patients understand the practical benefit of treatments like statins or antihypertensives. For example, an NNT of 50 means that 50 patients must be treated for a specified period to prevent one cardiovascular event. Lower NNT values indicate more effective interventions.
Usage
Usage note: Always specify the time period and endpoint when reporting NNT values.
In Context
- "The NNT for statin therapy in primary prevention is approximately 100 over five years." — Clinical evidence review
- "Shared decision-making tools often present NNT data to help patients understand treatment benefits." — Patient counseling guideline