Three parameters of lung function are reported: forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and the ratio of these measurements (FEV1/FVC).
In general, poor lung function was higher among those in the lowest income households, living in the most deprived areas, or with a household reference person with a semi-routine/routine occupation.
Lung function was considerably worse in current smokers than in people who had never smoked cigarettes regularly. Ex-smokers who had stopped smoking more than 10 years ago had similar lung function to those who never smoked, but more
recent ex-smokers had similar results to current smokers. The amount smoked was also an important factor: lung function decreased as lifetime cigarette consumption increased.