Objective To determine risk factors associated with the prevalence of chronic obstructive pulmonary disease (COPD) in urban and rural populations in Chengdu. Methods A multistage random cluster sampling method was adopted to select participants from four communities in Chengdu. All residents aged 40-70 yr. were eligible to participate in this study, which involved a questionnaire survey, physical examination and portable spirometry. Those with airflow limitations were also given post-bronchodilator testing 15 min after inhalation of a dose of 200 μg salbutamol. We defined a forced expiratory volume in one second/forced vital capacity (FEV1/FVC) of less than 70% as COPD. Logistic regression models were performed to identify risk factors of COPD. Results Of a total of 1 931 eligible participants, 1 579 (81.77%) completed the questionnaire and spirometry. About 8.35% were identified with COPD: 7.69% in urban vs. 12.37% in rural (\P\P\P\P
