Relative Outcome Risk

Synonyms

Cumulative incidence ratio; Relative risk

Definition

The risk ratio (RR) of an event is the risk of the outcome in the treatment group (or exposed group) divided by the risk in the control group (or unexposed group). RR is an example of exposure effects used in connection with dichotomous outcomes. When the exposure factor under study is a risk factor $\text{RR} > 1$. $\text{RR} = 1$ when there is no association between exposure and disease. $\text{RR}<1$corresponds to a protective exposure. In relative risk regression models, where regression coefficients for main effects exposure variables have an interpretation of log relative risk, a significant interaction between exposure and a second variable means that the second variable is an effect modifier. Logistic regression and multiplicative Cox regression are all examples of multiplicative models for which the relative risk is the implicit...