Understand sensitivity and specificity (Section 5.3).

Sensitivity and specificity are important metrics in determining the accuracy of a diagnostic test. Sensitivity is the ability of a test to correctly identify patients with a condition or disease (true positives), while specificity is the ability of a test to correctly identify patients without the condition or disease (true negatives). Higher sensitivity means fewer false negatives, meaning fewer cases of the disease are missed. Lower specificity means more false positives, meaning more people who don't have the disease are incorrectly identified as having it. Both values should be considered when evaluating a diagnostic test, as a high sensitivity without corresponding specificity, or vice versa, can lead to inaccurate test results.