Overview of the analysis of thresholds in the relationships between the quantity of smoking and HRQoL in current daily smokers.

Thresholds and estimates of effects*. * Estimates adjusted for socioeconomic variables, CESD, BMI, co-intoxication and comorbidities. ** Threshold (estimate of effect) is shown; here for example, a man aged 25–44 loses 0.02SDS of physical functioning per cigarette smoked above 5 cig./day. *** There are two thresholds, with a plateau effect at the second threshold; here for example a man aged 25–44 gains 0.22 SDS for the bodily pain score per cigarette smoked up to 5 per day, plus loses 0.22 SDS per cigarette smoked above 5 cig./day.