Estimation of Cutoff Values of Cotinine in Urine and Saliva for Pregnant Women in Poland

Table 5

Optimized cutoff values of cotinine in saliva and urine for pregnant women (Youden’s index 0.956 ± 0.0084).

	Smoking		AUC∗	SE	95% CI	Cutoff	Sensitivity	Specificity
	Yes	No
Saliva						[ng/mL]
Trimester I	19	50	0.998	0.003	0.992–1.000	31.90	100%	96%
Trimester II	17	52	0.997	0.004	0.989–1.000	18.10	100%	96%
Trimester III	17	52	0.997	0.004	0.989–1.000	11.47	100%	96%
Trimesters II & III	34	104	0.997	0.003	0.992–1.000	12.85	100%	96%
Urine						[ng/mL]
Trimester II	17	52	0.997	0.004	0.989–1.000	53.00	100%	96%
Trimester III	17	52	0.991	0.008	0.976–1.000	34.44	100%	94%
Trimesters II & III	34	104	0.994	0.004	0.997–1.000	42.31	100%	95%
Urine corrected						[μg/g]
Trimester II	17	52	0.995	0.005	0.986–1.000	68.35	100%	96%
Trimester III	17	52	0.990	0.008	0.974–1.000	48.53	100%	94%
Trimesters II & III	34	104	0.993	0.004	0.984–1.000	53.09	100%	95%

^∗𝑃<0.0001.