Skip to main content
. 2022 Mar 30;12(3):e049646. doi: 10.1136/bmjopen-2021-049646

Table 2.

Smoking markers

Current smokers
(n=12)
Ex-smokers
(n=25)
Never smokers
(n=64)
P value
Pack years of smoking 2.13 (0.59–3.48) 2.13 (0.05–5.40) 0.00 (0.00–0.00) 0.467*
Breath CO (ppm) 9 (3.5–21) 2 (2–3) 1 (1–2) <0.001
Urine cotinine (ng/mL) 837 (22.42–1571.8) 22.42 (22.42–22.42) 22.42 (22.42–22.42) <0.001

Values presented as median (IQR).

*Comparison between current and ex-smokers only.

CO, carbon monoxide.