Statistically Significant
A finding mathematically unlikely to be the result of random chance or coincidence. Used to confirm that a pattern—like a disease cluster—is real and not just noise in the data.
Related terms
Epidemiology The branch of medicine that studies how often diseases occur in different groups of people and why. Epidemiologists are the disease detectives who investigate outbreaks and clusters. Observed vs. Expected Rates An epidemiological method of comparing the actual (observed) number of disease cases in a community against the number that would be expected based on state or national averages. A statistically significant gap suggests an environmental cause. Percentile A statistical ranking that shows what percentage of a group falls at or below a given value. Being in the 95th percentile for pollution exposure means only 5% of areas are more polluted.