Table 1.
Baseline characteristics of study subjects
| Fourth graders (aged 9 or 10 years) | Seventh graders (aged 12 or 13 years) | |||||
|---|---|---|---|---|---|---|
| Boys (n = 1,054) |
Girls (n = 990) |
P-valuea | Boys (n = 878) |
Girls (n = 828) |
P-valuea | |
| Age (years) | 9.3 (0.5) | 9.4 (0.5) | 0.460 | 12.3 (0.5) | 12.3 (0.5) | 0.858 |
| Height (cm) | 135.0 (5.8) | 134.8 (6.4) | 0.421 | 154.9 (8.1) | 152.9 (6.0) | < 0.001 |
| Weight (kg) | 31.6 (6.5) | 30.6 (6.2) | < 0.001 | 45.4 (10.4) | 44.0 (8.0) | 0.002 |
| BMI (kg/m2) | 17.2 (2.7) | 16.7 (2.4) | < 0.001 | 18.8 (3.3) | 18.7 (2.7) | 0.900 |
| %BF (%) | 19.2 (5.6) | 16.9 (5.4) | < 0.001 | 16.4 (5.9) | 20.8 (5.9) | < 0.001 |
| WC (cm) | 59.5 (7.7) | 58.5 (6.6) | 0.002 | 65.8 (9.2) | 65.3 (7.2) | 0.233 |
| Number of obesityb | 87 (8.3) | 31 (3.1) | < 0.001 | 53 (6.0) | 18 (2.2) | < 0.001 |
| Number of obesityc | 79 (7.5) | 29 (2.9) | < 0.001 | 51 (5.8) | 18 (2.2) | < 0.001 |
Values are means (SD) or number (%)
BMI, body mass index; %BF, percent body fat; WC, waist circumference; SD, standard deviation
aunpaired t-test or chi-squared test
bObesity is defined according to the obese definition of the Centers for Disease Control and Prevention
cObesity is based on the definition of obesity in Japanese children