Table 6.

Per cigarette nicotine and CO exposure while smoking usual brand and light cigarettes

Week 1 (usual brand)Week 2 (light)Week 3 (usual brand)Overall, PPost hoc P
Week 1 versus week 2Week 1 versus week 3
CPD22.527.522.90.010.020.97
Plasma nicotine/CPD (ng/mL)
    Mean0.840.680.820.11
    SD0.490.430.46
    95% CI(0.58-1.10)(0.45 0.90)(0.57 1.08)
Plasma cotinine/CPD (ng/mL)
    Mean11.99.613.00.030.190.53
    SD6.25.46.6
    95% CI(8.6 15.2)(6.7 12.5)(9.4 16.7)
COHb/CPD
    Mean0.240.180.270.0020.030.46
    SD0.120.090.13
    95% CI(0.18 0.31)(0.14 0.23)(0.20 0.34)
  • Abbreviation: 95% CI, 95% confidence interval.