| COPD status | Total+ | p-value§ | ||||
| Absent/mild | Moderate# | Severe¶ | ||||
| Subjects | 8634 | 425 | 331 | 9390 | ||
| Age yrs | 55.6±11.1 | 61.1±11.7 | 62.4±11.8 | 56.1±11.3 | 0.0001 | |
| Female | 4547 (52.7) | 192 (45.2) | 169 (51.1) | 4908 (52.3) | 0.0095 | |
| Ever worked in dusty job | 3132 (36.3) | 184 (43.3) | 173 (52.3) | 3489 (37.2) | 0.0001 | |
| Doctor-diagnosed COPDƒ | 490 (5.7) | 81 (19.1) | 127 (38.4) | 698 (7.4) | 0.0001 | |
| Doctor-diagnosed asthma## | 935 (10.8) | 100 (23.5) | 116 (35.0) | 1151 (12.3) | 0.0001 | |
| Doctor-diagnosed TB | 282 (3.3) | 33 (7.8) | 53 (16.0) | 368 ( 3.9) | 0.0001 | |
| Pre-BD PEF per Ht2 L·s−1·m−2 | 0.0001 | |||||
| ≤1.3 | 47 (0.5) | 39 (9.2) | 196 (59.2) | 282 (3.0) | ||
| >1.3–1.8 | 352 (4.1) | 139 (32.7) | 108 (32.7) | 599 (6.4) | ||
| >1.8–2.2 | 1000 (11.6) | 131 (30.8) | 21 (6.3) | 1152 (12.3) | ||
| >2.2 | 7235 (83.8) | 116 (27.3) | 6 (1.8) | 7357 (78.3) | ||
| Smoking history | 0.0001 | |||||
| Never | 3873 (44.9) | 96 (22.6) | 54 (16.3) | 4023 (42.8) | ||
| 0–10 pack-yrs | 612 (7.1) | 9 (2.1) | 6 (1.8) | 627 (6.7) | ||
| 10–20 pack-yrs | 848 (9.8) | 20 (4.7) | 15 (4.5) | 883 (9.4) | ||
| >20 pack-yrs | 3301 (38.2) | 300 (70.6) | 256 (77.3) | 3857 (41.1) | ||
| Biomass exposure h-yrs¶¶ | 16.9±56.2 | 16.7±52.9 | 26.1±61.4 | 17.3±56.3 | 0.0034 | |
| Cough/phlegm in last yr | 967 (11.2) | 88 (20.7) | 118 (35.7) | 1173 (12.5) | <0.0001 | |
| Wheeze in last yr | 1843 (21.4) | 194 (45.7) | 192 (58.0) | 2229 (23.7) | <0.0001 | |
| MRC dyspnoea score | 0.0001 | |||||
| 0 | 5964 (75.8) | 192 (52.0) | 86 (31.0) | 6242 (73.3) | ||
| 1 | 1077 (13.7) | 84 (22.8) | 53 (19.1) | 1214 (14.2) | ||
| 2 | 316 (4.0) | 40 (10.8) | 31 (11.2) | 387 (4.5) | ||
| ≥3 | 515 (6.5) | 53 (14.4) | 107 (38.6) | 675 (7.9) | ||
Data are presented as n, mean±sd or n (%), unless otherwise stated. COPD: chronic obstructive pulmonary disease; TB: tuberculosis; BD: bronchodilator; PEF: peak expiratory flow; Ht: height; MRC: Medical Research Council. #: post-BD forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) below the lower limit of normal (LLN) and FEV1 <80% predicted. ¶: post-BD FEV1/FVC<LLN and FEV1 <60% predicted. +: sites included Guangzhou, China; Adana, Turkey; Salzburg, Austria; Reykjavik, Iceland; Cape Town, South Africa; Krakow, Poland; Hannover, Germany; Bergen, Norway; Vancouver, Canada; Manila, Philippines; Lexington, KY, USA; Sydney, Australia; London, UK; Uppsala, Sweden. §: two-tailed p-value based on Pearson’s Chi-squared test for categorical data or t-test for continuous data. ƒ: patient ever told by a healthcare provider that they have chronic bronchitis, emphysema or COPD. ##: patient ever told by a healthcare provider that they have asthma, asthmatic bronchitis or allergic bronchitis. ¶¶: highly skewed, so p-value is based on transformed biomass exposure variable.