Table 2.

Binary classification test

		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)

Allows calculations for determining how well a test or practice compares with reality or the gold standard.

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.