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 | |||||
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.