Which of the following are characteristics of an ideal screening test?

• A. High sensitivity.
• B. High specificity.
• C. Both High sensitivity and High specificity.
• D. Neither.

Answer: (C)

An ideal screening test would both catch almost every person who has the disease and correctly rule out those who don’t. This means high sensitivity (few false negatives) and high specificity (few false positives). With high sensitivity, you don’t miss cases, which is crucial in screening, especially for serious conditions. With high specificity, you avoid labeling healthy people as diseased, reducing unnecessary anxiety, follow-up tests, and costs. In practice, tests often trade off one for the other, but the best-case scenario is achieving both.