Table 1. Characteristics of study population at baseline (n = 120, 40/group).
| Obese a | Normal a | Lean a | P-value | |
|---|---|---|---|---|
| School ID, n (%) b | 0.087 | |||
| 1 | 20(48.8%) | 8(19.5%) | 13(31.7%) | |
| 2 | 12(24.5%) | 20(40.8%) | 17(34.7%) | |
| 3 | 8(26.7%) | 12(40%) | 10(33.3%) | |
| Age (mean±SD, y) c | 8.6±0.3 | 8.6±0.3 | 8.5±0.4 | 0.732 |
| Height (mean±SD, cm) c | 133.2±4.9 | 132.5±4.9 | 132.6±5.1 | 0.761 |
| Weight (mean±SD, kg) c | 36.9±7.6 | 28.6±3.0 | 24.3±2.5 | 0.000 |
| BF% (mean±SD) c | 26.4±3.4 | 17.9±1.5 | 14.1±0.9 | 0.000 |
| Age at breast II (95% C.I.) c | 8.8(8.6–8.9) d | 9.2(8.9–9.5) | 9.3(8.9–9.6) | 0.023 |
| Stage of Breast, n (%) b | 1.000 | |||
| I | 27(67.5%) | 27(67.5%) | 27(67.5%) | |
| II | 13(32.5%) | 13(32.5%) | 13(32.5%) |
a. Obese, normal, and lean groups were classified according to body fat percent (%) using skinfold thickness.
b. Chi square test of independence were used to compare the difference among the three groups.
c. ANOVA and least significant difference (LSD) analyses were used to compare the means among the three groups.
d. Post hoc tests were used to compare the difference between obese, normal, and lean girls. The mean age at breast II onset was earlier in obese girls than normal (P = 0.04) and lean girls(P = 0.02).