Do sensitivity and specificity change with prevalence of the disease?

The correct answer is that neither sensitivity nor specificity changes with the prevalence of the disease. Sensitivity refers to the ability of a test to correctly identify individuals who have the disease (true positives), while specificity denotes the ability of a test to correctly identify those who do not have the disease (true negatives).

Both sensitivity and specificity are inherent properties of a diagnostic test; they depend on the test's design, the biological characteristics of the disease, and not on how common or rare the disease is in a given population. Therefore, regardless of whether the prevalence of a disease is high or low, the sensitivity and specificity values remain constant.

It’s important to distinguish this from concepts such as positive predictive value and negative predictive value, which are affected by disease prevalence. As prevalence increases, the positive predictive value often increases, while the negative predictive value often decreases; however, this is not the case for sensitivity and specificity.