Skip to main content

Table 1 Inclusion and exclusion criteria

From: Respiratory effects of particulate air pollution episodes in former smokers with and without chronic obstructive pulmonary disease: a panel study

Inclusion criteria Exclusion criteria
COPD Group Control Group All Groups
Former smoker Former smoker Active smoking
≥10 pack year smoking history, quit at least 3 months prior to enrollment ≥10 pack year smoking history, quit at least 3 months prior to enrollment Any significant pulmonary disease other than COPD which would limit the interpretability of the pulmonary function measures
Age 40-85 Age 40-85  
Moderate or severe COPD: Spirometry without evidence of airflow obstruction COPD exacerbationa in the prior six weeks
FEV1/FVC below the lower limit of normal and FEV1 < 70 % predicted for age and height No evidence of emphysema on CT imaging, if previously obtained Currently taking ≥10 mg a day of prednisone or equivalent systemic corticosteroid
Inability to perform exhaled breath condensate, spirometry, or complete respiratory symptom questionnaire
Pregnant or intending to become pregnant
  1. a An acute exacerbation of COPD was defined as a sustained worsening of the patient’s condition, from the stable state and beyond normal day-to-day variations, that is acute in onset and necessitates a change in regular medication in a patient with underlying COPD [30]