Prevalence of chronic obstructive pulmonary disease according to demographic criteria
| Studies n | Cumulative prevalence % (95% CI) | p-value | |
| All | 37 | 7.6 (6–9.5) | |
| Age | <0.0001 | ||
| <40 yrs | 9 | 3.1 (1.8–5) | |
| ≥40 yrs | 34 | 9.9 (8.2–11.8) | |
| 40–64 yrs | 23 | 8.2 (6.5–10.3) | |
| ≥65 yrs | 11 | 14.2 (11–18) | |
| Status | <0.0001 | ||
| Active smoker | 17 | 15.4 (11.2–20.7) | |
| Ex-smoker | 16 | 10.7 (8.1–14) | |
| Nonsmoker | 16 | 4.3 (3.2–5.7) | |
| Sex | 0.0002 | ||
| Male | 27 | 9.8 (8–12.1) | |
| Female | 27 | 5.6 (4.4–7) | |
| Geographic zone | 0.77 | ||
| Africa | 0 | ||
| America | 3 | 4.6 (2.8–7.6) | |
| Europe | 28 | 7.4 (5.9–9.3) | |
| South-east Asia | 2 | 11.4 (4.4–26.4) | |
| Pacific | 4 | 9 (3–24.1) | |
| Sample | 0.04 | ||
| Urban | 12 | 10.2 (7.4–13.9) | |
| Rural | 4 | 8 (3.9–15.8) | |
| Mixed | 21 | 6.1 (4.9–7.7) |
Modified and reproduced from [14] with permission from the publisher.