TABLE 2 Electronic nose 1 validation set: performance characteristics of volatile organic compound analysis for children with lower respiratory tract symptoms

	Mean AUC (95% CI)	p-value	Sensitivity	Specificity	+LR	−LR
Rhinovirus positive
Acute infection^#	0.77 (0.07)	<0.001	73.0	96.0	18.25	0.28
Recovered^¶	0.84 (0.06)	<0.001	84.0	75.9	3.49	0.21
Rhinovirus negative
Acute infection^#	0.81 (0.05)	<0.001	75.6	71.4	2.64	0.34
Recovered^¶	0.67 (0.06)	0.005	62.9	65.6	1.83	0.57

Sensitivities, specificities, and positive (+LR) and negative likelihood ratios (−LR) are reported for the respective optimum cut-points. Symptomatic infection was defined as the presence of expiratory wheeze as assessed by auscultation. Asymptomatic infections were defined as children never experiencing respiratory symptoms severe enough to consult a general practitioner. Recovered infections were defined as children with confirmed wheeze who were tested again after resolution of their first symptomatic infection. AUC: area under the curve. ^#: symptomatic versus asymptomatic; ^¶: ex-symptomatic versus asymptomatic.