Specificity

Related: Sensitivity

• The specificity is the proportion of patients without the event that are classified as low risk

$$\text{Specificity}=\frac{TN}{TN+FP}$$

• Specificity (aka true negative rate) is defined as $p(\text{test result}=0|\text{actual event}=0)$, i.e., the probability of a negative test given that the truth is negative.
• The False Positive Rate is defined as one minus the specificity, i.e. $\text{FPR}=1-\text{Specificity}$.