The CanCOLD will be the first study to assess prevalence of disease across Canada and its consequence in men and women, and to evaluate a conceptual model of disease severity based on patient's health perception (health-related quality of life). Ultimately, this project will extend to a longitudinal follow up (3 years or beyond) and will allow to have a better understanding of the lifestyle risk factors, not only smoking but also diet, physical activity, and co morbid conditions. This will be a great asset to shift from management of a single risk factor (tobacco control) to total COPD risk management. The results of the study will greatly help to assist decision makers in developing policies to improve the diagnosis, the management of COPD and to optimize health care services use.