Table 1. Mean values (s.d.), minimum and maximum values and number of missing values of selected variables among 262 Norwegian girls.
| Variables | Mean (s.d.) | Range | Missing (n) |
|---|---|---|---|
| At birth | |||
| Birth weight (g) | 3463 (476) | 2420–4710 | 0 |
| Birth length (cm) | 50.0 (1.8) | 42.0–55.8 | 3 |
| Ponderal index (g cm−3) | 2.76 (0.26) | 2.09–4.18 | 3 |
| Head circumference (cm) | 34.8 (1.2) | 31.9–38.0 | 2 |
| Skin-fold thickness (mm) | 4.4 (1.0) | 2.2–7.9 | 3 |
| Gestational age (days) | 282.6 (7.1) | 264.0–294.0 | 0 |
| In adolescence | |||
| Age (years) | 14.0 (0.7) | 12.7–15.5 | 0 |
| Weight (kg) | 54.5 (9.9) | 33.9–96.4 | 2 |
| Height (cm) | 162.9 (6.8) | 143.0–183.5 | 1 |
| BMI (kg/m2) | 20.5 (3.0) | 14.3–32.0 | 2 |
| Waist/hip ratio | 0.78 (0.06) | 0.63–1.26 | 1 |
| Age at menarche (years)a | 13.1 (0.1) | 9.5–14.5 | 6 |
| Maternal | |||
| Age at menarche (years) | 13.0 (1.4) | 10.0–17.0 | 0 |
a
Median age at menarche (standard error), calculated by the use of Kaplan–Meier survival analysis.