Table 3

Repeatability within subject of lung function parameters expressed as within subjects variation coefficient (standard deviation within the two best/mean of the two best%)

FVCa
 FEV1 b
 FEV0.75 c
 FEV0.5 d
 MEF75 e
 MEF50 f
 MEF25 g
N
 458
 576
 680
 766
 458
 458
 458
Mean (%)
 2.0
 2.2
 2.2
 2.1
 6.0
 9.1
 16.3
Max (%)
 12.4
 13.6
 13.7
 14.1
 51.9
 51.9
 92.3
0–5% (%)
 90.8
 90.8
 92.1
 90.9
 65.0
 41.1
 23.9
6–10% (%)
 8.1
 8.5
 7.5
 8.4
 19.4
 33.5
 20.2
10%+ (%)
 1.1
 0.7
 0.4
 0.8
 15.6
 25.3
 56.0

aFVC = forced vital capacity;

bFEV1= forced expiratory volume in one second;

cFEV0.75 = forced expiratory volume in 3/4 of a second;

dFEV0.5 = forced expiratory volume in half a second;

eMEF75 = instantaneous expiratory flow when 25% of FVC has to be expired

fMEF50 = instantaneous expiratory flow when 50% of FVC has to be expired

gMEF25 = instantaneous expiratory flow when 75% of FVC has to be expired

Piccioni et al. Respiratory Research 2007 8:14   doi:10.1186/1465-9921-8-14