Table 1.

Binary classification and formulas for calculating predictive values of modalities such as animal-based research.

		Gold Standard
		GS+	GS-
Test	T+	TP	FP
	T-	FN	TN
Sensitivity = TP/(TP+FN)
Specificity = TN/(FP+TN)
Positive Predictive Value = TP/(TP+FP)
Negative Predictive Value = TN/(FN+TN)
T- = Test negative T+ = Test positive FP = False positive TP = True positive FN = False negative TN = True negative GS- = Gold standard negative GS+ = Gold standard positive