Table 1.
Geometric mean exhaled carbon monoxide (COex) level by certain baseline characteristics among 512 785 participants
| Baseline characteristics | Men |
Women |
||
|---|---|---|---|---|
| No. | Mean (95% CI) COex, ppm | No. | Mean (95% CI) COex, ppm | |
| Age group in yearsa | ||||
| 30–39 | 29 590 | 8.4 (8.3–8.5) | 48 201 | 3.2 (3.2–3.2) |
| 40–49 | 59 221 | 8.8 (8.8–8.9) | 93 503 | 3.2 (3.2–3.2) |
| 50–59 | 63 700 | 7.8 (7.8–7.9) | 93 815 | 3.3 (3.2–3.3) |
| 60–69 | 41 317 | 6.2 (6.2–6.3) | 50 436 | 3.2 (3.2–3.2) |
| 70–79 | 16 348 | 5.1 (5.1–5.2) | 16 654 | 3.1 (3.1–3.1) |
| Regionb | ||||
| Urban | 91 338 | 6.7 (6.3–6.7) | 134 839 | 3.0 (3.0–3.0) |
| Rural | 118 838 | 7.6 (7.6–7.7) | 167 770 | 3.4 (3.4–3.4) |
| Educational levelc | ||||
| No formal school | 18 654 | 7.5 (7.4–7.7) | 76 543 | 3.1 (3.1–3.1) |
| Primary school | 70 085 | 7.4 (7.3–7.4) | 95 080 | 3.2 (3.2–3.2) |
| Middle school | 68 162 | 7.4 (7.4–7.5) | 76 728 | 3.3 (3.3–3.3) |
| High school | 36 723 | 6.9 (6.8–6.9) | 40 797 | 3.3 (3.2–3.3) |
| College/university | 16 552 | 5.7 (5.7–5.8) | 13 461 | 3.1 (3.1–3.1) |
| Household income (Yuan/year)c | ||||
| <10 000 | 54 712 | 7.3 (7.3–7.4) | 90 061 | 3.2 (3.2–3.3) |
| 10 000–19 999 | 59 544 | 7.3 (7.2–7.3) | 89 443 | 3.2 (3.2–3.2) |
| 20 000–34 999 | 53 395 | 7.0 (7.0–7.1) | 73 310 | 3.1 (3.1–3.2) |
| ≥35 000 | 42 525 | 6.9 (6.8–6.9) | 49 795 | 3.2 (3.2–3.2) |
| Overall | 210 176 | 7.2 (7.2–7.3) | 302 609 | 3.1 (3.1–3.1) |
aAdjusted for area.
bAdjusted for age at survey, and rural/urban area.
cAdjusted for age at survey and area.