Table 4.
Specific tracking coefficient (partial correlation coefficient controlled for age and maturation) between the values at the first measurements and the subsequent measurements and tracking or stability coefficient estimated from generalized estimated equation for body mass index for Ellisras rural children
| Preschool children | Primary school children | ||||
|---|---|---|---|---|---|
| Mean age (years) | Boys | Girls | Mean age (years) | Boys | Girls |
| 4.9 | 0.53** | 0.46** | 8.5 | 0.48** | 0.52** |
| 5.5 | 0.51** | 0.25** | 9.1 | 0.40** | 0.39** |
| 5.9 | 0.42** | 0.23** | 9.6 | 0.26** | 0.28** |
| 6.5 | 0.34** | 0.18* | 10.1 | 0.24** | 0.23** |
| 6.9 | 0.21** | 0.21* | 10.6 | 0.22** | 0.20** |
| 7.5 | 0.23** | 0.18* | 11.0 | 0.22** | 0.21** |
| 7.9 | 0.22** | 0.19* | 11.6 | 0.20** | 0.21** |
| 8.5 | 0.25** | 0.17* | 12.0 | 0.13* | 0.22** |
| 8.9 | 0.21** | 0.16* | 12.5 | 0.22** | 0.20** |
| 9.9 | 0.16* | 0.15* | 13.5 | 0.13* | 0.20** |
| 10.9 | 0.16* | 0.17* | 14.5 | 0.12* | 0.18** |
| 11.5 | 0.20* | 0.17* | 14.9 | 0.13* | 0.19** |
| Stability | -0.01 | 0.61 | Stability | 0.10 | 0.55 |
| 95% CI | -0.01-0.001 | 0.56-0.66 | 95% CI | 0.08-0.12 | 0.50-0.59 |
*p<0.05;
**<0.001; Stability=Longitudinal tracking coefficient estimated using GEE; 95% CI=Confidence interval; GEE=Generalized estimating equation