13C-Urea breath test threshold calculation and evaluation for the detection of Helicobacter pylori infection in children

Table 1 Results of the ¹³ C-UBT in children and adolescents^*

Patients and Methods
Sample Collection Time [Minutes]	30	60	30	60	30	30	30	30	30	30	60
Age Limits [Years]					0.3–5	5–8	8–11	11–14	14–18
Number of Tests	251	251	251	251	138	289	383	278	137	1223	1232
Method of Analysis	LR	LR	BM	BM	BM	BM	BM	BM	BM	BM	BM
Histology used	Yes	Yes	Yes	Yes	No	No	No	No	No	No	No
Threshold Results
Threshold from Logistic Regression (LR) [‰Δδ]	5.29	6.76
SD [‰Δδ]	0.3	0.5
R² LR	0.91	0.85
Threshold from Specificity [‰Δδ]			5.66	6.72	9.10	5.57	6.83	6.46	4.97	5.78	6.19
SD [‰Δδ]					4.46	1.22	0.86	1.05	1.46	0.45	0.42
Positive plus Negative Predictive Values [‰Δδ]			5.54	6.53	12.25	7.78	8.11	7.24	5.56	7.19	7.55
SD [‰Δδ]					5.10	1.66	1.00	1.19	1.76	0.56	0.53
Performance Results
Sensitivity	0.95	0.93	0.91	0.94	0.94	0.91	0.98	0.98	0.97	0.96	0.96
Specificity	0.97	0.95	0.96	0.97	0.95	0.94	0.98	0.97	0.96	0.96	0.95
Positive predictive value	0.97	0.96	0.95	0.97	0.95	0.94	0.98	0.98	0.96	0.96	0.95
Negative predictive value	0.95	0.92	0.89	0.92	0.98	0.97	0.99	0.99	0.98	0.99	0.99
AUROC	0.94	0.98	0.98	0.99	0.98	0.97	0.99	0.99	0.99	0.99	0.99

^*Mean results from bootstrapping. Empty fields: not applicable. BM: Binormal maximum likelihood modeling. LR: Logistic regression. SD: Standard Deviation. UBT: Urea Breath Test. AUROC: Area under the receiver operator characteristic curve.

ISSN: 1471-230X