Population characteristics
| Boys | Girls | ||||
| N | % | N | % | ||
| BMI-based weight categories | Obese | 244 | 6.4 | 179 | 4.7 |
| Overweight | 741 | 19.5 | 668 | 17.6 | |
| Normal weight | 122 | 3.2 | 179 | 4.7 | |
| Underweight | 2699 | 70.9 | 2765 | 72.9 | |
| Are you trying to lose weight? | No, I am happy with my weight | 2998 | 79.8 | 2206 | 58.3 |
| No, but I need to lose weight | 423 | 11.3 | 760 | 20.1 | |
| Yes | 338 | 9 | 819 | 21.6 | |
| Weight concern/dieting | Unnecessary concern but not dieting in normal weight/underweight (UC) | 146 | 4 | 440 | 12.4 |
| Unnecessary concern and dieting in normal weight/underweight (UD) | 95 | 2.6 | 455 | 12.8 | |
| Weight concern and dieting in overweight/obese (HD) | 241 | 6.7 | 331 | 9.3 | |
| Lack of concern, no dieting in overweight/obese (LC) | 714 | 19.8 | 483 | 13.6 | |
| Lack of concern, no dieting in normal weight/underweight (reference) | 2413 | 66.9 | 1835 | 51.8 | |
| Body size perception | Very fat | 58 | 1.6 | 122 | 3.2 |
| Quite fat | 676 | 18.1 | 1008 | 26.6 | |
| Like others | 721 | 19.3 | 534 | 14.1 | |
| Quite thin | 66 | 1.8 | 41 | 1.1 | |
| Very thin | 2212 | 59.3 | 2080 | 55.0 | |
| Body size perception | BSP underestimation | 687 | 19.8 | 455 | 13.0 |
| BSP overestimation | 585 | 16.8 | 783 | 22.3 | |
| BSP accurate | 2204 | 63.4 | 2272 | 64.7 | |
| Mental distress (SCL-5) | Low mental distress (score <2) | 3251 | 89.8 | 2715 | 73.0 |
| High mental distress (score >2) | 361 | 10.2 | 1002 | 27.0 | |
BMI-based weight categories are age and sex adjusted in accordance with Cole et al.23 24
BMI, body mass index; BSP, body size perception; HD, healthy dieting; LC, lack of weight concern; MD, mental distress; SCL-5, five-item Hopkins Symptom Checklist; UC, unnecessary weight concern; UD, unnecessary dieting.