Number needed to treatBMJ 2009; 338 doi: https://doi.org/10.1136/bmj.b2493 (Published 24 June 2009) Cite this as: BMJ 2009;338:b2493
- John Fletcher, clinical epidemiologist
- 1BMJ, London WC1H 9JR
Two weeks after entry to a trial of antibiotics to treat symptoms of chest infection, 25% of people receiving placebo and 15% of people receiving antibiotics still had symptoms. What is the number needed to treat in this trial for antibiotics to cure symptoms at two weeks?
a—Number needed to …