Specificity and sensitivity

Sensitivity and specificity are measures used to evaluate the accuracy of a diagnostic test. Sensitivity indicates how well the test identifies true positives—patients with the condition—meaning a highly sensitive test catches most actual cases. Specificity measures how well the test identifies true negatives—patients without the condition—minimizing false alarms. High sensitivity is crucial for screening tools to ensure few cases are missed, while high specificity is important to avoid false positives, reducing unnecessary worry or treatment. Together, they help understand a test's reliability in detecting or ruling out a condition accurately.