From: Urban–rural disparity in the relationship between ambient air pollution and preterm birth
Variable | Hubei | East | Middle | West |
---|---|---|---|---|
Total | 429,865 | 228,603 | 138,310 | 62,952 |
GA (weeks) | ||||
Mean (Std) | 39.24 (1.27) | 39.32 (1.26) | 39.14 (1.25) | 39.17 (1.32) |
< 37 | 2.98 | 2.91 | 2.94 | 3.32 |
Residence types | ||||
City propera | 31.98 | 40.04 | 23.04 | 22.36 |
County town | 10.45 | 9.94 | 9.10 | 15.24 |
Suburb | 9.10 | 13.68 | 4.90 | 1.70 |
General town | 41.19 | 31.81 | 58.65 | 36.89 |
Countryside | 7.28 | 4.53 | 4.31 | 23.81 |
PM2.5 exposure (30 μg/m3) | ||||
Mean (Std) | 3.10 (1.18) | 3.63 (1.21) | 2.87 (0.61) | 1.69 (0.53) |
Nationality | ||||
Han (Main)a | 96.89 | 99.63 | 99.35 | 81.55 |
Minority | 3.11 | 0.37 | 0.65 | 18.45 |
Age (years) | ||||
Mean (Std) | 26.83 (4.50) | 26.95 (4.49) | 26.60 (4.32) | 26.91 (4.93) |
< 20 | 2.29 | 1.95 | 2.08 | 3.96 |
20–24 | 30.49 | 29.85 | 32.04 | 29.39 |
25–29a | 43.98 | 44.22 | 44.72 | 41.50 |
30–34 | 16.49 | 17.13 | 15.38 | 16.65 |
≥ 35 | 6.75 | 6.85 | 5.79 | 8.49 |
Educational level | ||||
Elementary | 19.30 | 21.21 | 15.44 | 20.85 |
Secondarya | 74.79 | 70.70 | 81.20 | 75.55 |
Tertiary | 5.91 | 8.09 | 3.36 | 3.59 |
Frequency of health checks | ||||
< 5a | 78.31 | 63.25 | 95.19 | 95.91 |
≥ 5 | 21.69 | 36.75 | 4.81 | 4.09 |
Parity | ||||
Firstborn | 75.41 | 73.38 | 81.01 | 70.45 |
Non-Firstborna | 24.59 | 26.62 | 18.99 | 29.55 |
Infant sex | ||||
Malea | 54.07 | 54.72 | 53.82 | 52.28 |
Female | 45.93 | 45.28 | 46.18 | 47.72 |
Income (1,000 CNY) | ||||
Mean (Std) | 14.32 (7.20) | 15.89 (8.15) | 13.69 (4.82) | 9.98 (5.75) |