Figure 3From: Greater severity of new onset asthma in allergic subjects who smoke: a 10-year longitudinal studyPercentage of subjects with optimal ("Controlled"; white bars) and suboptimal ("Partly Controlled" and "Uncontrolled"; grey bars) asthma control among the non-smokers and those who smoked. Estimation of the amount and duration of smoking exposure was established by calculating pack-years. Smokers were therefore categorized by incremental pack-years.Back to article page