Table 5. The results of the ROC curve analysis.

Test variable	State variable	AUC	SE	P	95% CI
					Lower	Upper
Graft failure	PI	0.462	0.034	0.259	0.395	0.529
	MGF	0.575	0.034	0.026	0.509	0.641
	H0	0.720	0.028	<0.001	0.666	0.775
	H1	0.766	0.027	<0.001	0.713	0.820
	H0/H1	0.625	0.033	<0.001	0.561	0.690
	P	0.707	0.029	<0.001	0.650	0.763
MACCE	PI	0.475	0.035	0.466	0.406	0.543
	MGF	0.562	0.035	0.074	0.494	0.630
	H0	0.542	0.033	0.220	0.477	0.608
	H1	0.516	0.035	0.633	0.448	0.585
	H0/H1	0.500	0.035	0.994	0.431	0.568
	P	0.474	0.034	0.444	0.406	0.541
Repeat revascularization	PI	0.556	0.049	0.254	0.460	0.652
	MGF	0.571	0.049	0.146	0.474	0.668
	H0	0.563	0.047	0.196	0.471	0.656
	H1	0.508	0.046	0.864	0.419	0.598
	H0/H1	0.450	0.048	0.302	0.356	0.543
	P	0.630	0.048	0.008	0.537	0.724
MI	PI	0.525	0.065	0.691	0.398	0.652
	MGF	0.520	0.064	0.754	0.394	0.645
	H0	0.573	0.066	0.241	0.443	0.704
	H1	0.520	0.060	0.752	0.402	0.638
	H0/H1	0.524	0.062	0.706	0.402	0.645
	P	0.631	0.062	0.037	0.509	0.752

MACCEs, major adverse cardiac and cerebrovascular events; MI, myocardial infarction; AUC, area under the curve; SE, standard error; CI, confidence interval. PI, pulse index; MGF, mean graft flow; H₀, the amplitude of the main wave; H_1, the amplitude of the first harmonic; P, the frequency of the first harmonic.