Table 4

Percentage of smokers by different smoking criteria (regular smokers, smoked today or yesterday) and by different cut off points in serum cotinine level

North KareliaKuopio provinceSouth western FinlandHelsinki capital areaTotalχ2
2 test between the areas.
Regular smokers283132p=0.33*
Occational smokers7892930
Smoked today or yesterday30333588
Cotinine 10+3336403032p=0.12
Cotinine 15+3236403335.7P=0.009
Cotinine 20+3235393335p=0.013
Cotinine 50+2732343234.4p=0.008
Regular smokers1214192417p<0.001
Occational smokers78697
Smoked today or yesterday1417222620p<0.001
Cotinine 10+1819233023
Cotinine 15+1718232922p<0.001
Cotinine 20+1718222921p<0.001
Cotinine 50+1415202518p<0.001