Number needed to treat (NNT) is the number of patients who must be treated with an intervention for a specific period to prevent 1 bad outcome or result in 1 good outcome. What is the reciprocal of the NNT? Use your mouse to highlight the answer:

Absolute risk reduction, which is the proportion in the control group experiencing an event minus the proportion in the intervention group experiencing an event, is the reciprocal of the NNT.

See §20.9 for a Glossary of Statistical Terms.—Laura King, MA, MFA, ELS