Table 1 Clinical characteristics of the asthmatic adults
Clinical characteristicValue
Age (n = 328)
    Mean (SD) (years)37.3 (13.3)
Sex (n = 328)
    Men, %50.9
Four-class asthma severity score* (n = 328) (%)
    Class 132.6
    Class 222.6
    Class 315.2
    Class 429.6
Five-level asthma score* (n = 314) (%)
    Level 015.0
    Level 110.2
    Level 211.8
    Level 316.2
    Level 418.1
    Level 528.7
Treatment (n = 328)
    Inhaled corticosteroids (%)54.3
FEV1 % predicted (n = 325)
    Mean (SD)93.3 (20.8)
    FEV1 <80% predicted (%)22.8
Bronchial hyper-responsiveness (n = 166)
    PD20 ⩽4 mg (%)74.1
  • *For definitions, see methods.

  • PD20, provocative dose of methacholine causing a 20% fall in FEV1.

  • FEV, forced expiratory volume.