Understanding Sensitivity and Specificity

Positive Predictive Value (PPV)

• The probability that a person with a positive result has a disease or condition.

• The probability that a person with a negative result has a disease or condition.

• The probability that a person without a disease has a positive result.

• The probability that a person with a disease will test negative.

Specificity

• The ability to correctly identify those who have a positive result.

• The ability to correctly identify those who have a negative result.

• The ability to identify all individuals regardless of their results.

• The ability to measure the accuracy of a test.

False Positive

• A test result that correctly identifies a positive case.

• A test result that incorrectly indicates a positive when it is actually negative.

• A test result that is inconclusive.

• A test result that shows no signs of the condition.

Sensitivity

• The ability to correctly identify those who have a positive result.

• The ability to correctly identify those who have a negative result.

• The ability to measure the severity of a condition.

• The ability to predict future outcomes based on past data.

False Negative

• A result that states it is negative when the result is actually positive.

• A result that states it is positive when the result is actually negative.

• A result that is inconclusive and cannot be determined.

• A result that accurately reflects the true condition.

Negative Predictive Value (NPV)

• The probability that a person with a negative result does not have the disease or condition.

• The probability that a person with a positive result has the disease or condition.

• The probability that a person with a negative result has the disease or condition.

• The probability that a person with a positive result does not have the disease or condition.