Definitions for **"Absolute risk reduction"**

a measure of treatment effect that compares the probability (or mean) of a type of outcome in the control group with that of a treatment group, [i.e.: Pc - Pt (or Ã‚Âµc - Ã‚Âµt)]. For instance, if the results of a trial were that the probability of death in a control group was 25% and the probability of death in a treatment group was 10%, the absolute risk reduction would be (0.25 - 0.10) = 0.15. (See also number needed to treat, odds ratio, and relative risk reduction.)

The absolute arithmetic difference in events rates, ( EER- CER).

( ARR) the difference in the absolute risk (rates of adverse events) between study and control populations. ( Therapy) To Calculation