Analysis of agreement between expired-air carbon monoxide monitors

This study explored the level of agreement in expired air carbon monoxide values measured with the Vitalograph BreathCO or the Bedfont piCO+ Smokerlyzer. Expired air samples were taken from 78 adult nicotine-dependent smokers who were participating in studies using carbon monoxide values to confirm abstinence or no abstinence durations of 12 or 24 hours.