How is relative risk calculated?

Relative risk is calculated by comparing the incidence of a condition in a group that has been exposed to a specific risk factor with the incidence of the same condition in a group that has not been exposed. This comparison provides a measure of the strength of the association between exposure and the outcome.

When calculating relative risk, the focus is on the ratio of the proportion of individuals who develop the condition in the exposed group to the probability of developing the condition in the unexposed group. A relative risk greater than one indicates that the exposure increases the risk of the condition, while a value less than one suggests a protective effect of the exposure. This method is particularly useful in epidemiological studies to establish a link between risk factors and health outcomes.