Fig. 4From: The prevalence, burden and risk factors associated with chronic obstructive pulmonary disease in Commonwealth of Independent States (Ukraine, Kazakhstan and Azerbaijan): results of the CORE studyPoint prevalence of COPD stratified by age. The prevalence of COPD was calculated per 1000 persons and expressed with 95% confidence intervals in three age groups: 18–39, 40–64, and ≥65 years old, for previously diagnosed COPD (when self-reported by the respondent while completing the study questionnaire) and COPD diagnosed by spirometry (confirmed by spirometry results based on GOLD Guidelines (2011), i.e. FEV1/FVC < 0.70)Back to article page