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Number needed to treat (NNT)

Understand the model, recognise it in a stem, separate the look-alikes, then apply it.

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Watch it explainedThe drug helped thirty percent more. You still treat seven to help one.
Visual explanationUse the diagram to rebuild the concept from memory.
ARR = 20% − 12% = 8% → NNT = 1 / 0.08 ≈ 13 20% Control (CER) 12% Treated (EER) event rate (%)
From event rates to NNT
01Memory anchor
NNT = 1 / ARR, and ARR = Control − Experimental.

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