relative risk

Syllable breakdown

Dictionary meaning

also called the risk ratio, relative risk is the ratio of the probability of an outcome occurring in an exposed group to the probability of the same outcome in an unexposed group, and is the primary measure of association in cohort studies and randomised controlled trials where incidence can be directly calculated; a relative risk of 2.0 indicates that exposed individuals are twice as likely to experience the outcome as unexposed individuals, while a relative risk of 0.5 indicates a 50 percent reduction in risk associated with exposure; relative risk is more interpretable than the odds ratio when outcomes are common, because the odds ratio overstates the magnitude of association in such circumstances; communicating relative risk alongside absolute risk difference is essential for accurate public understanding of health findings, since a large relative risk may reflect a very small absolute difference if the baseline risk is low