Anthropometric and demographic sample characteristics: (mean (SD) or percentage)
| Girls (n = 194) | Boys (n = 205) | Total sample (n = 399) | |
| Age, years, months | 8.28 (0.62) | 8.27 (0.65) | 8.28 (0.64) |
| BMI, kg/m2 | 16.57 (2.73) | 16.47 (2.54) | 16.52 (2.63) |
| BMI, SD* | 0.12 (1.40) | 0.12 (1.31) | 0.12 (1.35) |
| BMI, centile | 52.68 (34.93) | 51.38 (34.40) | 52.01 (34.62) |
| Weight category† | |||
| % Underweight | 14.9 (n = 29) | 17.1 (n = 35) | 16 (n = 64) |
| % ⩽50th Centile but not underweight | 30.4 (n = 59) | 31.7 (n = 65) | 31.1 (n = 124) |
| % >50th Centile but not overweight | 35.6 (n = 69) | 33.2 (n = 68) | 34.3 (n = 137) |
| % Overweight | 12.9 (n = 25) | 13.7 (n = 28) | 13.3 (n = 53) |
| % Obese | 6.2 (n = 12) | 4.4 (n = 9) | 5.3 (n = 21) |
| Ethnicity | |||
| % White | 42.8 (n = 83) | 43.9 (n = 90) | 43.4 (n = 173) |
| % Non-white | 52.1 (n = 101) | 52.2 (n = 107) | 52.1 (n = 208) |
| % Ethnicity missing | 5.2 (n = 10) | 3.9 (n = 8) | 4.5 (n = 18) |
| Area deprivation level‡ | 4.33 (3.46) | 4.28 (3.54) | 4.31 (3.50) |
*SD score based on British 1990 norms.18 †Based on International Obesity Taskforce Criteria with additional subdivision of lower and higher healthy weight groups.19 ‡Area deprivation measured using the Townsend index.17 BMI, body mass index.