Table 4– Characteristics of American Thoracic Society/European Respiratory Society quality measurements in groups defined by visual acceptability#
Visually acceptableVisually unacceptablep-valueTotal
Subjects n22628713133
BEV L0.07 (0.05)0.08 (0.07)<0.00010.07 (0.05)
BEV % FVC2.70 (1.16)3.88 (2.41)<0.00012.92 (1.47)
Difference FEV1 L0.04 (0.05)0.05 (0.09)<0.00010.04 (0.06)
Difference FVC L0.04 (0.06)0.06 (0.09)<0.00010.05 (0.07)
FET s3.95 (2.39)2.30 (2.06)<0.00013.54 (2.63)
  • Data are presented as median (interquartile range), unless otherwise stated. BEV: back-extrapolated volume; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; FET: forced expiratory time. #: n=3133 healthy children from the LUNOKID study; : differences between groups using Wilcoxon rank sum test.