Table 2.

Sample population covariate frequencies

Age
Mean	Min	Max
35.8	13	77
Smoke status
Never	Previous	Current
176	60	83
Sex
Variable	Freq	Percent (%)
Female	165	51.7
Male	154	48.3
Medication usage
Variable	Freq	Percent (%)
General lung medication	48	15.0
Betamimetica	37	11.6
Inhaled corticosteroids	26	8.2