Sensitivity and Specificity

The positive rate of the test in the group with disease (true positive rate) is called the sensitivity of the test, and the negative rate of the test in the group without disease (true negative rate) is called the specificity. It would be ideal if a certain value (cutoff) could completely separate the presence and absence of disease, but such a thing is practically impossible. There will be people who are determined to be positive even though they are essentially negative. Such persons (who are not ill) are very concerned about their diagnosis. In such cases, further detailed testing will be done to proceed with the diagnosis. It is difficult for patients to understand the sensitivity and specificity.