Table 1.
Baseline descriptive characteristics of participants
| Variable | Mean | sd | n |
|---|---|---|---|
| Age (yr) | 6.4 | 1.6 | 76 |
| Breast stagea | |||
| Stage 1 | NA | NA | 71 |
| Stage 2 | NA | NA | 3 |
| Stage 3 | NA | NA | 1 |
| Anthropometrics | |||
| Weight (kg) | 25.8 | 8.4 | 73 |
| Height (cm) | 120.0 | 11.8 | 73 |
| BMI | 17.5 | 3.2 | 73 |
| BMI-for-age percentile | 69.0 | 28.3 | 73 |
| % body fatb | 27.3 | 9.8 | 73 |
| FFST mass (kg)b | 16.8 | 4.3 | 73 |
| BMC (g)b | |||
| Total body | 859.7 | 262.5 | 73 |
| Lumbar spine | 17.8 | 4.8 | 73 |
| Proximal femur | 10.7 | 4.0 | 72 |
| Forearm | 2.4 | 0.8 | 73 |
| 25(OH)D (nmol/liter) | 88.3 | 24.5 | 74 |
| IGF-I (ng/ml) | 251.3 | 94.1 | 76 |
| Dietary Intake | |||
| Vitamin D (μg)c | 6.34 | 2.34 | 73 |
| Calcium (mg) | 861.0 | 355.0 | 73 |
| Physical activityd | 3.5 | 0.8 | 73 |
NA, Not applicable.
a
Sexual maturation stage (breast) as described by Tanner (31).
b
Body fat percentage, fat-free soft tissue mass, and bone mineral content measured by DXA.
c
Vitamin D (in micrograms) is presented using the geometric mean ± geometric sd [exp(arithmetic mean of ln-transformed data) ± exp(usual sd of ln-transformed data)].
d
Physical activity level assessed by parent questionnaire developed by Slemenda et al. (38): 1, inactive; 2, below average; 3, average; 4, above average; 5, very high.