TABLE 3

Mixed linear models on differences in D_LNO and secondary end-points between MasterScreen and HypAir devices

Variables	Coefficient	95% CI	p-value
Primary end-point
D_LNO mL·min⁻¹·mmHg⁻¹	24.0	21.7 to 26.3	<0.0001
Secondary end-points
D_LCO mL·min⁻¹·mmHg⁻¹	−0.03	−0.57 to 0.12	0.20
Alveolar volume L	0.48	0.45 to 0.52	<0.0001
Breath-hold time s	−0.33	−0.42 to −0.24	<0.0001
Inspiratory volume L	0.008	−0.028 to 0.026	0.66
κNO s⁻¹	−1.08	−1.21 to −0.94	<0.0001
κCO s⁻¹	−0.0035	−0.004 to −0.003	<0.0001
K_NO mL·min⁻¹·mmHg⁻¹·L⁻¹	2.2	1.9 to 2.5	<0.0001
K_CO mL·min⁻¹·mmHg⁻¹·L⁻¹	−0.41	−0.46 to −0.37	<0.0001
ΔFANO ppm	−4.40	−5.15 to −3.66	<0.0001
ΔFACO %	−0.015	−0.016 to −0.013	<0.0001
NO, expired/inspired ratio	−0.017	−0.012 to −0.014	<0.0001
O₂, expired/inspired ratio	0.012	0.005 to 0.019	0.0014
CO, expired/inspired ratio	−0.007	−0.012 to −0.002	0.0063
He, expired/inspired ratio	−0.054	−0.058 to −0.050	<0.0001

Data are presented as mean (95% confidence interval). Positive coefficients means that HypAir gave larger measurements than MasterScreen. D_LCO: diffusing capacity of the lung for CO; D_LNO: diffusing capacity of the lung for NO; κCO: permeability factor for CO; κNO: permeability factor for NO; K_NO: transfer coefficient of the lung for NO; K_CO: transfer coefficient of the lung for CO; FACO: fractional concentration of CO from the alveolar space; FANO: fractional concentration of NO from the alveolar space; ΔFACO (expired–inspired CO concentration); ΔFANO (expired–inspired NO concentration). Ratios of expired to inspired gas concentrations are also shown.