Table 1.

Equations Used for Confusion Matrix Analysis of Subject RCW Wear-Time Diary Data vs Adherence Monitor Electronic Data.

Matrix measure	Equation	Result range
Precision	$=\frac{TP}{TP+FP}$	0 ≤ precision ≤ 1
Sensitivity (recall, TPR)	$=\frac{TP}{TP+FN}$	0 ≤ sensitivity ≤ 1
MCC accuracy	$=\frac{\left(TP*TN\right)-(FP*FN)}{Sqrt\left(\left(TP+FP\right)*\left(TP+FN\right)*\left(TN+FP\right)*\left(TN+FN\right)\right)}$	–1 ≤ MCC ≤ 1

Abbreviations: TPR, true-positive rate; MCC, Matthews correlation coefficient; Sqrt, square root; True positive (TP), when the diary and sensor algorithms agree the RCW was worn. True negative (TN), when both agree the RCW was not worn. False positive (FP), when the sensor algorithm indicates the RCW is being worn but diary indicates the RCW was not worn. False negative (FN), when the sensor algorithm indicates the RCW is not worn, but the diary indicates the RCW was worn.