Table 1—

The reference sample selected according to American Thoracic Society criteria, included 1,282 males (M) and 1,510 females (F), and represented the 5% random sample of the total population

CriteriaPrevalence %Number excludedNumber remaining
Unacceptable spirometry2.72.6345212481458
Current smokers29.530.0375449499722
MD diagnosis of asthma5.15.42240477682
MD diagnosis of chronic bronchitis3.92.358472674
Self-reported ever-asthma8.58.51714455660
Wheezing or breathlessness during last 12 months13.312.32935426625
Persistent cough17.015.25252374573
Difficulty in breathing of any cause7.87.51018365555
Age >80 yrs2.02.439362546
  • MD: Doctor of Medicine

  • M: males

  • F: females