TABLE 4

Differences in in vivo functional residual capacity (FRC) measurements from body plethysmography FRC on each device

	Subjects n	WIMR		EM		ndd v2.00		ndd v2.01
	Subjects n	Absolute	Relative	Absolute	Relative	Absolute	Relative	Absolute	Relative
Controls	20	−0.13±0.46^#	−3.3±13.0%	0.17±0.41	4.7±11.8%	−0.73±0.36	−20.6±8.9%	−0.36±0.32	−10.1±8.4%
Asthmatics	9	−0.24±0.45	−6.8±13.8%	0.01±0.39	0.12±12.0%	−0.73±0.59	−20.7±15.3%	−0.42±0.57	−11.2±15.8%
All subjects	29	−0.17±0.45	−4.4±13.1%	0.12±0.40	3.3±11.8%	−0.73±0.43	−20.6±11%	−0.38±0.40	−10.5±10.9%

Data presented as mean±sd, unless otherwise stated. Absolute measurements are in litres. WIMR: Woolcock in-house device; EM: Exhalyzer D device; ndd v.2.00: EasyOne Pro LAB device Version 2.00.01.05; ndd v.2.01: EasyOne Pro LAB device analysed in Version 2.01.00.09. ^#: missing data for one subject.