Table 3.
Results of the mixed linear model for the dependent variable IGFBP-3
| Effect | Parameter estimate | se | P value |
|---|---|---|---|
| Intercept | 7.132 | 1.040 | <0.0001 |
| Tanner I | −0.362 | 0.444 | 0.0026 |
| Tanner II | −1.268 | 0.520 | 0.0158 |
| Tanner III | −1.457 | 0.644 | 0.0052 |
| Age (Tanner I) | 0.319 | 0.110 | 0.0282 |
| Age (Tanner II) | 0.088 | 0.173 | 0.0609 |
| Age (Tanner III) | 0.156 | 0.234 | 0.0505 |
| Age (Tanner IV and V) | −0.413 | 0.171 | 0.1065 |
| Fat mass | −0.012 | 0.026 | 0.6347 |
| Lean mass | 0.226 | 0.102 | 0.0277 |
| Sex | 0.121 | 0.091 | 0.1901 |
| E2 | 0.007 | 0.013 | 0.5960 |
| Testosterone | 0.018 | 0.012 | 0.1258 |
| Ethnicity | −0.228 | 0.090 | 0.0127 |
Significant effects are in bold type. All continuously distributed variables were log transformed to correct for skewed distributions. Ethnicity and sex were coded in the models as follows: EA = 0; AA = 1; male = 0; female = 1. Age (Tanner), The age nested in the TS variable was used to account for changes in age within each TS.