Table 2.

MtDNA copy number in peripheral blood discrimination potential in different age groups: c-statistics

Age quartiles	AUC (95% CI)	p	Youden index	Sensitivity (%)	Specificity (%)	OR (95% CI)	Adj. OR (95% CI)
Q1 (< 31.42 years)	0.88 (0.80–0.97)	< 0.001	128	79	84	20.05 (5.70–70.58)	20.80 (5.72–75.64)
Q2 (31.42–33.27 years)	0.73 (0.60–0.86)	0.001	106	92	50	12.00 (3.35–43.04)	15.02 (3.82–59.11)
Q3 (33.28–35.97 years)	0.65 (0.52–0.78)	0.024	109	66	64	3.49 (1.33–9.21)	3.68 (1.32–10.25)
Q4 (> 35.97 years)	0.67 (0.55–0.79)	0.015	117	45	88	6.07 (1.62–22.67)	5.82 (1.51–22.43)

Q quartile, AUC area under the ROC curve, CI confidence interval, ROC receiver operating characteristics, OR odds ratio for subfertility, Adj. OR odds ratio for subfertility adjusted for parity