• Specificity (%) = 100 × |

• Highly specific tests are used to rule-in a diagnosis, as these tests are unlikely to yield false-positive results.

• Sensitivity is the proportion of diseased individuals with a positive test result.

• The positive predictive value is the probability that someone with a positive test result actually has the disease.

• The negative predictive value is the probability that someone with a negative test result does not have the disease.