Table 2.
Means in height (cm) and multiple comparisons for mean differences for boys and girls among four regions of residence, stratified by age groups.
| Age groups (yr) | Big citya | Small-medium cityb | Ordinary rural areac | Poor rural aread | F | P | Pab | Pac | Pad | Pbc | Pbd | Pcd |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean (95% CI) | Mean (95% CI) | Mean (95% CI) | Mean (95% CI) | |||||||||
| Boys | ||||||||||||
| 6–8 | 126.15 (123.67–128.62) | 126.37 (124.05–128.69) | 121.23 (120.17–122.30) | 124.30 (122.84–125.77) | 9.952 | <0.0001∗∗ | 1.000 | <0.0001∗∗ | 0.900 | <0.0001∗∗ | 0.689 | 0.011∗ |
| 9–11 | 140.58 (138.50–142.66) | 142.51 (140.69–144.32) | 136.98 (135.68–138.27) | 134.66 (132.04–137.28) | 11.686 | <0.0001∗∗ | 1.000 | 0.108 | 0.003∗ | <0.0001∗∗ | <0.0001∗∗ | 0.357 |
| 12–14 | 160.59 (158.22–162.95) | 158.06 (156.18–159.95) | 155.84 (154.40–157.29) | 152.35 (150.13–154.56) | 8.950 | <0.0001∗∗ | 0.930 | 0.019∗ | <0.0001∗∗ | 0.467 | 0.001∗ | 0.031∗ |
| 15–18 | 172.91 (170.35–175.47) | 169.93 (168.41–171.45) | 168.59 (167.53–169.66) | 168.64 (167.21–170.06) | 4.387 | 0.005∗ | 0.203 | 0.004∗ | 0.010∗ | 0.997 | 1.000 | 1.000 |
| Girls | ||||||||||||
| 6–8 | 120.52 (118.36–122.68) | 125.35 (123.69–127.02) | 120.12 (119.01–121.23) | 121.57 (119.60–123.54) | 7.637 | <0.0001∗∗ | 0.002∗ | 1.000 | 1.000 | <0.0001∗∗ | 0.037∗ | 1.000 |
| 9–11 | 142.23 (140.08–144.38) | 142.53 (140.54–144.52) | 137.56 (136.16–138.97) | 137.83 (136.11–139.55) | 8.625 | <0.0001∗∗ | 1.000 | 0.006∗ | 0.043∗ | <0.0001∗∗ | 0.006∗ | 1.000 |
| 12–14 | 157.66 (155.88–159.45) | 155.35 (153.72–156.98) | 153.57 (152.47–154.68) | 150.01 (146.81–153.1) | 7.813 | <0.0001∗∗ | 1.000 | 0.060 | <0.0001∗∗ | 1.000 | 0.003∗ | 0.029∗ |
| 15–18 | 159.35 (157.25–161.44) | 159.61 (157.99–161.23) | 158.05 (157.24–158.86) | 157.08 (155.39–158.78) | 2.495 | 0.060 | n/a | n/a | n/a | n/a | n/a | n/a |
Note. ∗p < 0.05; ∗∗p < 0.0001. Post hoc multiple comparisons were conducted. Bonferroni adjustment was used for post hoc multiple comparisons. Pab shows p value for the test of the mean difference between big city and small-medium city; Pac shows p value for the test of the mean difference between big city and ordinary rural; Pad shows p value for the test of the mean difference between big city and poor rural; Pbc shows p value for the test of the mean difference between small-medium city and ordinary rural; Pbd shows p value for the test of the mean difference between small-medium city and poor rural; Pcd shows p value for the test of the mean difference between ordinary rural and poor rural.