Table 6 Two different validation methods of smoking history by measuring carbon monoxide (CO)/ppm in the breath of randomly selected Polish immigrants (n = 90)
From: Smoking characteristics of Polish immigrants in Dublin
1) Inter-quartile Range of CO/ppm | Heavy smokers | Light smokers | p = 0.001 | ||
No | % | No | % | ||
2–9 | 3 | 8.8 | 20 | 35.7 | |
10–22 | 12 | 35.3 | 24 | 42.9 | |
23–63 | 19 | 55.9 | 12 | 21.4 | |
2) Correlation between CO levels in ppm and the number of cigarettes smoked | |||||
r = 0.64 | p < 0.0001 | ||||