Specificity

Specificity - (in screening tests) see Sensitivity.

The specificity of a test measures how accurately it can identify healthy people who do not actually have the disease. The higher the specificity of the test, the lower the likelihood of false positive results.

Specificity is calculated using the formula:

Specificity = True Negatives / (True Negatives + False Positives)

Where:

True negatives are the number of healthy people correctly identified by the test as not having the disease.

False positives are the number of healthy people incorrectly identified by a test as having the disease.

Thus, specificity shows the proportion of truly healthy people among all those identified by the test as healthy. The higher the specificity, the lower the likelihood of a false alarm.

Specificity is the ability of a test or method to identify only those who have a particular disease or condition, rather than those who just happen to have similar symptoms.

For example, if a patient has high cholesterol in the blood, this does not mean that he necessarily has coronary heart disease. In order to accurately determine the presence or absence of coronary heart disease, it is necessary to conduct additional studies and tests.

The specificity of a test determines how accurately it can identify those who actually have the disease, rather than just those who have symptoms similar to those of the disease. The higher the specificity of the test, the less likely it is to make an error in diagnosis.