Which statement about specificity and confirmatory tests is true?

Which statement about specificity and confirmatory tests is true?

• A. High specificity reduces false negatives
• B. High specificity reduces false positives
• C. High specificity increases false positives
• D. High specificity has no impact on test accuracy

Answer: (B)

Specificity is the test’s ability to correctly identify people who do not have the condition. When specificity is high, most healthy individuals test negative, so the number of false positives is small. That’s why a highly specific test is effective for confirmation: it minimizes wrongly labeling healthy people as diseased after an initial positive result. This concept focuses on false positives, not false negatives—that's the domain of sensitivity. So the statement that high specificity reduces false positives is true. The other options mix up what specificity affects or ignore the trade-offs with sensitivity and overall accuracy.

Specificity is the test’s ability to correctly identify people who do not have the condition. When specificity is high, most healthy individuals test negative, so the number of false positives is small. That’s why a highly specific test is effective for confirmation: it minimizes wrongly labeling healthy people as diseased after an initial positive result. This concept focuses on false positives, not false negatives—that's the domain of sensitivity. So the statement that high specificity reduces false positives is true. The other options mix up what specificity affects or ignore the trade-offs with sensitivity and overall accuracy.