Baseline characteristics of participants by sex and region types (figures in the column are % of total)
| Characteristics | Men | Women | ||
|---|---|---|---|---|
| Rural (%) N=118 837 | Urban (%) N=91 220 | Rural (%) N=167 727 | Urban (%) N=134 711 | |
| Height (mean±SD in cm) | 164.1±6.3 | 166.8±6.5 | 153.2±5.9 | 155.3±5.9 |
| Age (years) | ||||
| 30–39 | 14.5 | 13.5 | 18.2 | 13.1 |
| 40–49 | 27.7 | 28.8 | 31.4 | 30.2 |
| 50–59 | 31.2 | 29.1 | 31.2 | 30.7 |
| 60–69 | 19.8 | 19.5 | 15.0 | 18.8 |
| 70–79 | 6.8 | 9.1 | 4.2 | 7.2 |
| Mean (SE) | 52.6 (0.03) | 53.1 (0.04) | 50.5 (0.02) | 52.6 (0.03) |
| BMI (kg/m2) | ||||
| <18.5 | 5.7 | 2.8 | 5.2 | 3.2 |
| 18.5 to <25 | 71.5 | 55.3 | 64.3 | 57.9 |
| ≥25 | 22.7 | 41.8 | 30.5 | 38.9 |
| Mean (SE) | 22.7 (0.01) | 24.3 (0.01) | 23.5 (0.01) | 24.3 (0.01) |
| Smoking status | ||||
| Never smoker | 11.3 | 18.4 | 94.4 | 95.5 |
| Occasional smoker | 11.0 | 11.5 | 2.0 | 1.6 |
| Ex-regular smoker | 11.8 | 15.3 | 0.9 | 0.8 |
| Current regular smoker | 65.9 | 54.8 | 2.6 | 2.1 |
| Pack years* | ||||
| <10 | 19.7 | 19.3 | 47.7 | 51.7 |
| 10–20 | 23.1 | 26.3 | 26.5 | 25.1 |
| >20 | 57.1 | 54.5 | 25.8 | 23.2 |
| Mean (SE) | 26.7 (0.07) | 24.8 (0.07) | 15.2 (0.2) | 13.7 (0.22) |
| Age started smoking (years) | ||||
| <20 | 34.7 | 33.1 | 35.1 | 21.9 |
| 20–24 | 38.0 | 36.6 | 21.4 | 16.6 |
| 25–29 | 12.5 | 15.8 | 12.2 | 12.4 |
| ≥30 | 14.8 | 14.6 | 31.4 | 49.1 |
| Number of cigarettes smoked daily (or equivalent) | ||||
| 1–4 | 7.2 | 4.7 | 29.1 | 24.9 |
| 5–14 | 27.5 | 30.8 | 47.2 | 51.3 |
| 15–24 | 45.1 | 47.8 | 20.4 | 20.7 |
| ≥25 | 20.2 | 16.7 | 3.3 | 3.1 |
| Reason for stopping among ex-smokers | ||||
| Physical illness | 53.2 | 45.9 | 64.1 | 40.8 |
| Other reason | 46.8 | 54.1 | 35.9 | 59.2 |
| Exposure to passive smoking† | 73.7 | 63.0 | 87.5 | 83.2 |
| Highest education completed | ||||
| No formal education | 12.7 | 4.0 | 31.7 | 17.3 |
| Primary school | 43.8 | 19.7 | 40.4 | 20.3 |
| Middle or high school | 41.8 | 60.5 | 27.2 | 53.3 |
| College or university | 1.7 | 15.9 | 0.6 | 9.2 |
| Household income (yuan/year) | ||||
| 2500–4999 | 14.3 | 2.6 | 15.1 | 4.1 |
| 5000–9999 | 23.5 | 8.0 | 26.1 | 11.5 |
| 10 000–19 999 | 28.9 | 27.6 | 28.9 | 30.4 |
| ≥20 000 | 33.3 | 61.7 | 29.9 | 54.1 |
| Exposure to cooking fuels‡ | ||||
| Currently cooks with coal/wood | 27.7 | 5.3 | 81.0 | 8.7 |
| Ever cooked with coal/wood | 32.7 | 33.6 | 92.6 | 61.0 |
| Currently cooks with gas/electricity | 7.1 | 56.5 | 12.4 | 83.6 |
| Respiratory symptoms | ||||
| Chronic cough and phlegm | 7.3 | 6.2 | 2.6 | 1.8 |
| Breathlessness | 5.8 | 3.4 | 8.5 | 4.7 |
*Restricted to ever regular smokers.
†Defined as never smokers who lived with a smoker or were exposed at work for 1–5 days/week or daily.
‡Restricted to participants who reported cooking daily or weekly.
BMI, body mass index.