specificity
The ability of a screening test to correctly identify individuals who do not have the disease (true negative rate).
Full Definition
Specificity is a statistical measure that describes how well a screening test correctly identifies people who do not have the disease being tested for. It is calculated as the number of true negatives divided by the sum of true negatives and false positives. A test with high specificity produces few false positive results, meaning it rarely incorrectly identifies healthy individuals as having the disease. Specificity is typically expressed as a percentage and is complementary to sensitivity in evaluating test performance.
Usage
Usage note: Often confused with sensitivity. Remember: specificity identifies true negatives, sensitivity identifies true positives.
In Context
- "The mammography screening program achieved a specificity of 92%, resulting in a false positive rate of 8%." — Research paper
- "High specificity is crucial for screening tests to minimize unnecessary anxiety and follow-up procedures." — Clinical assessment