Case control feasibility study assessing the association between severity of coronary artery disease with Glutathione Peroxidase-1 (GPX-1) and GPX-1 polymorphism (Pro198Leu)

Table 5 Receiver operating characteristic curves generated optimum cut-off values for coronary artery disease risk markers with severity of CAD scoring systems

Cut-off values	(%) SE 95 % CI	(%) SP 95 % CI	(%) PPV 95 % CI	(%) NPV 95 % CI	PLR 95 % CI	NLR 95 % CI	AUC 95 % CI	P value
Vessel score
GPX-1	97	61	73	96	2.5	0.04	0.931	0.000
23.9 (U/g Hb)	86–99	43–77	59–84	78–99	1.7–3.8	0.0–0.3	0.867–0.995	0.000
Stenosis score
GPX-1	91	42	42	91	1.6	0.20	0.768	0.000
23.9 (U/g Hb)	73–99	28–56	29–57	72–99	1.2–2.0	0.0–0.7	0.651–0.885	0.000
Extent score
GPX-1	78	43	63	61	1.4	0.5	0.681	0.007
23.9 (U/g Hb)	63–90	25–61	49–76	38–80	1.0–1.9	0.2–1.0	0.558–0.805	0.007

AUC Area under curve, 95 % CI 95 % confidence interval, NLR Negative likelihood ratio, NPV Negative predictive value, PLR Positive likelihood ratio, PPV Positive predictive value, SE Sensitivity, SP Specificity; Significant at p < 0.05

ISSN: 1471-2261