odds ratio
The odds ratio is a measure of the odds of an event happening in one group compared to the odds in another group. Usually seen in case-control (retrospective) studies to determine if a certain exposure is associated with a risk of a particular outcome. An odds ratio of one means there is likely no change in risk of a particular outcome or event. An odds ratio of greater than one means there is an increased risk and less than one means that the exposure reduces the risk.
