Table 3. Diagnostic performance for skin prick test and IgE to peanut, ROC analysis.

Test	Cutoff point	Unadjusted OR (95% CI)	p value	Sensitivity (%)	Specificity (%)	PPV (%)	NPV (%)	AUC
SPT (mm)	3	4.68 (2.32–9.41)	<0.0001	91.5	30.5	85.7	43.9	64.8
	4	7.30 (3.92–13.6)	<0.0001	87	52.5	89.3	47	68.1
	5	7.78 (4.22–14.4)	<0.0001	81.4	64.4	91.3	43.2	67.2
	6	7.75 (4.12–14.6)	<0.0001	74.7	72.9	92.6	38.7	65.7
	7	9.10 (4.55–18.2)	<0.0001	68.4	81.4	94.4	36.1	65.2
	8	9.75 (4.52–21.0)	<0.0001	61.7	86.4	95.4	33.1	64.3
	9	9.91 (4.23–23.2)	<0.0001	54.7	89.8	96.1	30.3	63.2
	10	7.64 (3.06–19.0)	<0.0001	43.5	91.5	95.9	26.2	61.1
Peanut IgE (kU/L)	0.35	1.96 (0.63–6.11)	0.2438	91	15.4	89.7	17.4	53.5
	2	3.50 (1.54–7.97)	0.0028	75.2	53.9	92.9	21.2	57.1
	5	3.07 (1.30–7.26)	0.0106	58.6	69.2	93.9	17.1	55.5
	6	7.41 (2.97–18.5)	<0.0001	42.8	91.5	95.8	26	60.9
	7	6.97 (2.80–17.4)	<0.0001	41.3	91.5	95.7	25.5	60.6
	8	7.79 (2.88–21.1)	<0.0001	38.7	93.2	96.3	25	60.6
	9	6.53 (2.41–17.7)	0.0002	34.6	93.2	95.9	23.8	59.8
	10	3.75 (1.31–10.8)	0.0138	42.9	84.6	95.7	15.5	55.6
	20	6.07 (1.12–32.9)	0.0364	26.2	96.2	98.2	13.9	56.1
	30	12.6 (0.73–218)	0.0819	19.1	100	100	13.3	56.6
	40	9.30 (0.53–164)	0.1275	14.8	100	100	12.7	56.3
	50	7.29 (0.41–130)	0.1770	11.9	100	100	12.3	56.2

IgE, immunoglobulin E; ROC, receiver operating characteristic; OR, odds ratio; CI, confidence interval; SPT, skin prick test; PPV, positive predictive value; NPV, negative predictive value; AUC, area under the receiver operator characteristic curve.