When aiming to confirm a disease, which test property should be prioritized?

• A. High sensitivity.
• B. High negative predictive value.
• C. High specificity.
• D. High positive predictive value.

Answer: (C)

When you want to confirm that someone has a disease, you need a test that minimizes false positives. High specificity does exactly that, so a positive result is most trustworthy for ruling in the disease. In other words, a highly specific test gives you strong confidence that a person truly has the condition, reducing the chance of mislabeling healthy individuals as diseased. By comparison, high sensitivity is valuable for ruling out disease with a negative result, because it catches most true cases. Predictive values depend on how common the disease is in the population, so while this matters, specificity is the key property for confirmation.