Table 1. Cross correlation results for normal, arrhythmogenic and morphology changing signals with different values of correlation factors.

MEA recording from hiPSC-CMs	CF	TP	FP	TN	FN	PPV	Sensitivity	Specificity
Normal signal
Baseline	0.88	136	2	0	0	98.55%	100%	–
	0.93	136	2	0	0	98.55%	100%	–
	0.98	136	0	2	0	100%	100%	100%
Morphology changing signal
E-4031 400 nM + Esmolol – 84 µM	0.88	38	20	0	0	65.52%	100%	–
	0.93	38	6	14	0	86.36%	100%	70%
	0.98	38	2	18	0	95%	100%	90%
Arrhythmogenic signal
E-4031 – 700 nM	0.88	59	27	0	0	68.61%	100%	–
	0.93	59	7	20	0	89.39%	100%	74.07%
	0.98	59	3	24	0	95.16%	100%	88.89%

CF-Correlation factor, TP-True positive, FP-False positive, TN-True negative, FN-False negative, PPV-Positive predictive value.

From the table, it can be seen that PPV and specificity show significant improvement with an increase in CF. Experimental results have shown that CF between the ranges of 0.96–0.98 produce consistent results.