title: The socioeconomic status of subjects: a prominent feature contributing to the phenotypical approach to COPD.
authors.forename: R W
authors.initials: RW
authors.lastname: Dal Negro
mesh_terms: D006801:Humans; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology; D012923:Social Class