Body & HealthMental model

How many must take a treatment for one to benefit?

The Number Needed to Treat (NNT) answers exactly that. If a treatment cuts an event from 5 % to 4 %, the absolute difference is 1 % – the NNT is 100: a hundred people take it, one is spared. Statins for preventing heart attacks are in that range; some preventive measures and vaccines against rare diseases have an NNT above 1,000.

Useful: The NNT reveals what a relative percentage hides.

Source: en.wikipedia.org

Denkwerkzeug Statistik

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