TABLE 2

Percentages of healthy and wheezy children with spirometric data below the lower limit of normal (i.e. with z-score values according to Lille reference equations <−1.64)

HealthyWheezyChi-squared
p-value
Subjects n92#125
FVC4 (4.3)16 (12.8)0.033
FEV13 (3.3)10 (8.0)0.146
FEV0.755 (5.4)29 (23.2)<0.001
FEV0.55 (5.4)24 (19.2)0.003
FEV1/FVC4 (4.6)14 (11.2)0.071
FEV0.75/FVC5 (5.4)45 (36.0)<10−4
FEV0.5/FVC4 (4.3)29 (23.2)10−4
  • Data are presented as n (%), unless otherwise stated. FVC: forced vital capacity; FEVt: forced expiratory volume in t s. #: n=30 3-year-old children, n=31 4-year-old children and n=31 5-year-old children; : n=38 3-year-old children, n=38 4-year-old children and n=49 5-year-old children.