Table 1.
Changes over time in characteristics of children and their families in China, 1997–2011
| 1997 Mean (SD) |
2000 Mean (SD) |
2004 Mean (SD) |
2006 Mean (SD) |
2009 Mean (SD) |
2011 Mean (SD) |
Time trend, P valuea |
|
|---|---|---|---|---|---|---|---|
| Boys | |||||||
| N | 723 | 946 | 678 | 516 | 456 | 309 | |
| Age (years) | 10.0 (2.1) | 11.9 (2.7) | 12.4 (3.1) | 11.8 (3.2) | 11.8 (2.8) | 12.6 (2.3) | <0.0001 |
| Height (cm) | 134.5 (13.2) | 146.0 (16.2) | 150.0 (17.7) | 147.2 (18.9) | 148.8 (16.7) | 153.9 (14.8) | <0.0001 |
| Weight (kg) | 30.4 (8.6) | 38.6 (12.3) | 42.2 (14.1) | 40.1 (14.5) | 41.0 (13.9) | 45.5 (14.6) | <0.0001 |
| BMI (kg/cm2) | 16.5 (2.4) | 17.6 (2.7) | 18.1 (2.9) | 17.9 (3.1) | 18.0 (3.3) | 18.7 (3.7) | <0.0001 |
| Overweight and obesity (%) | 6.5 | 7.5 | 9.3 | 11.0 | 14.3 | 15.5 | <0.0001b |
| PA (METs/d) | 3.7 (4.9) | 5.9 (5.7) | 9.1 (10.8) | 7.5 (8.9) | 7.6 (8.6) | 7.1 (7.1) | <0.0001 |
| Sedentary (hrs/d) | 1.8 (1.1) | 1.5 (1.0) | 2.3 (1.4) | 2.5 (1.4) | 2.4 (1.5) | 2.1 (1.3) | <0.0001 |
| Energy (kcal) | 2033 (674.0) | 2121 (700.6) | 2150 (749.7) | 2044 (711.9) | 1958 (701.6) | 1953 (690.6) | <0.0001 |
| Family characteristics | |||||||
| Father BMI (kg/cm2) | 22.3 (2.7) | 22.7 (2.9) | 22.9 (3.1) | 23.0 (3.1) | 23.4 (3.3) | 23.9 (3.3) | <0.0001 |
| Mother BMI (kg/cm2) | 22.2 (2.6) | 22.6 (2.8) | 22.8 (3.0) | 23.0 (5.8) | 23.0 (3.2) | 23.1 (3.4) | <0.0001 |
| Father Education (years) | 8.2 (3.1) | 8.4 (2.9) | 8.7 (2.8) | 9.1 (3.0) | 8.8 (3.1) | 9.2 (3.0) | <0.0001 |
| Mother Education (years) | 6.7 (3.8) | 7.0 (3.7) | 7.7 (3.3) | 8.2 (3.3) | 8.0 (3.2) | 8.4 (3.2) | <0.0001 |
| Per capital family income (1000Yuan/Y) | 3.8 (3.0) | 4.6 (4.4) | 5.7 (5.5) | 6.7 (6.7) | 9.9 (10.5) | 11.7 (14.6) | <0.0001 |
| Urbanization index | 49.0 (16.9) | 53.9 (17.0) | 58.6 (19.4) | 60.8 (20.2) | 63.1 (19.6) | 67.1 (19.1) | <0.0001 |
| Girls | |||||||
| N | 606 | 836 | 603 | 463 | 384 | 279 | |
| Age (years) | 10.1 (2.1) | 11.9 (2.8) | 12.1 (3.0) | 11.9 (2.9) | 11.5 (2.8) | 12.6 (2.4) | <0.0001 |
| Height (cm) | 134.8 (13.4) | 144.2 (13.6) | 145.5 (15.1) | 145.2 (15.1) | 144.9 (14.6) | 149.5 (11.6) | <0.0001 |
| Weight (kg) | 30.3 (8.8) | 37.1 (10.8) | 38.6 (11.8) | 37.9 (11.4) | 37.8 (12.2) | 41.6 (11.7) | <0.0001 |
| BMI (kg/cm2) | 16.3 (2.2) | 17.4 (2.7) | 17.7 (2.9) | 17.6 (3.0) | 17.5(3.2) | 18.2(3.4) | 0.0149 |
| Overweight and obesity (%) | 4.6 | 4.8 | 7.0 | 7.3 | 9.2 | 10.4 | <0.0001b |
| PA (METs/d) | 3.4 (4.9) | 4.5 (5.1) | 6.7 (8.5) | 6.3 (8.2) | 4.5 (4.8) | 5.6 (4.7) | <0.0001 |
| Sedentary (METs/d) | 1.8 (1.2) | 1.6 (1.1) | 2.2 (1.3) | 2.3 (1.2) | 2.5 (1.5) | 2.2 (1.1) | <0.0001 |
| Energy (kcal) | 1872 (593.4) | 1887 (589.5) | 1810 (610.3) | 1861 (607.6) | 1669 (515.1) | 1696 (682.2) | <0.0001 |
| Family characteristics | |||||||
| Father BMI (kg/cm2) | 22.3 (2.8) | 22.8 (2.9) | 23.0 (3.0) | 22.9 (3.1) | 23.2 (3.6) | 23.8 (3.3) | <0.0001 |
| Mother BMI (kg/cm2) | 22.6 (2.9) | 22.6 (2.8) | 22.8 (3.2) | 23.0 (3.1) | 22.9 (3.4) | 22.8 (3.2) | <0.0001 |
| Father Education (years) | 8.1 (3.1) | 8.4 (2.9) | 9.0 (2.8) | 9.2 (3.1) | 8.6 (3.0) | 8.5 (3.2) | <0.0001 |
| Mother Education (years) | 6.4 (3.9) | 7.0 (3.7) | 7.7 (3.4) | 8.0 (3.7) | 8.0 (3.2) | 8.2 (3.2) | <0.0001 |
| Per capital family income (1000Yuan/Y) | 3.5 (2.7) | 4.6 (4.4) | 5.7 (5.5) | 6.5 (6.4) | 9.2 (10.4) | 10.6 (15.0) | <0.0001 |
| Urbanization index | 50.0 (17.3) | 54.8 (17.2) | 58.9 (19.4) | 61.2 (19.2) | 64.6 (18.7) | 68.6 (18.0) | <0.0001 |
a
Kruskal-Wallis Test
b
Chi-squared Test