Define analytic sensitivity and specificity.

• A. Sensitivity is the probability of disease given a positive test; Specificity is the probability of no disease given a negative test
• B. Specificity is the capacity to react to only one chemical
• C. Sensitivity is the lowest concentration the test can detect
• D. Sensitivity: detect the lowest concentration the test can detect; Specificity: capacity of a test to react to only one chemical

Answer: (D)

Understanding analytic sensitivity and analytic specificity means looking at how a lab test performs in detecting what it’s designed to measure, independent of disease status. Analytic sensitivity is about the smallest amount of the target analyte that the test can reliably detect—the limit of detection. Analytic specificity is the test’s ability to react to the target analyte while not reacting to other substances, i.e., it avoids cross-reactivity and responds only to the intended chemical.

This aligns with the option that states the test detects the lowest concentration it can detect and that it reacts to only one chemical. The other choices mix in concepts from clinical performance (disease presence given a test result) or only partly describe one aspect, which doesn’t capture the full analytic meaning.