Table 1

Reference sample selection criteria and characteristics of the study sample

Participants (White) interviewed n
 Less invalid spirometry data1185413554
 Less ever smokers46436845
 Less nonhealthy subjects31074195
 Less irreproducible data24973556
Age in years n
Age last birthday yrs40±15.743±17.0
Height cm176±6.8162±6.4
FEV1 L4.1±0.812.9±0.65
FVC L5.0±0.943.5±0.74
  • Data are presented as absolute values or mean±sem

  • FEV1: forced expiratory volume in one second

  • FVC: forced vital capacity