Table 1

 Experimental design*

End of week123456789101112
CigaretteOmni or own cigarettesOwn cigarettes or Omni
*Parentheses indicate samples collected but not analysed.
CO, carbon monoxide; NNAL/HOP, carcinogen metabolites; SOC, stage of change.
Cigarettes/dayx2x2x2x2x2X2x2x2x2x2x2x2
Cigarette buttsxxxxxx
Laboratory smokingxxxxxx
Craving, withdrawalxxxxxx
24 hour urine(x)(x)x(x)(x)x
SOCxx
Omni ratingx