Table 2.

Predictive ability of Stroke Assessment of Fall Risk at cut point score of 27 vs. Fall Harm Risk Screen at cut point score of two.

		Predicted outcomes
		Fall	No fall
Stroke Assessment of Fall Risk (cut point = 27)	Fall	TP, n = 52	FN, n = 15	Sensitivity = TP/(TP + FN) = 0.78
	No fall	FP, n = 128	TN, n = 222	Specificity = TN/(TN + FP) = 0.63
		PPV = TP/(TP + FP) = 0.29	NPV = TN/(TN + FN) = 0.94

		Predicted outcomes
		Fall	No fall
Fall Harm Risk Screen (cut point = 2)	Fall	TP, n = 39	FN, n = 29	Sensitivity = TP/(TP + FN) = 0.57
	No fall	FP, n = 170	TN, n = 181	Specificity = TN/(TN + FP) = 0.48
		PPV = TP/(TP + FP) = 0.19	NPV = TN/(TN + FN) = 0.86

FN: false negative; FP: false positive; NPV: negative predictive value; PPV: positive predictive value; TN: true negative; TP: true positive.