number needed to treat (NNT)

Related concepts: risk difference, absolute risk reduction, relative risk reduction and odds ratio The number of subjects treated per subject with a favourable outcome. Note: It is the inverse of absolute risk reduction (1 ÷ absolute risk reduction). Thus, if the results of a study indicate that the probability of death in a control group is 25% and the probability of death in a treatment group is 10%, the number needed to treat would be 1.0 ÷ (0.25 — 0.10) = 6.7, therefore 7 subjects.

and • provides information on costs and financial impact. Note 2: The report may optionally discuss organisational considerations. Note 3: A “mini-HTA” may be as rigorous as an HTA report but typically has a restricted scope and so is quicker to produce. Note 4: Related terms include health technology, HTA report, rapid review, level of evidence