Table 1. Sample characteristics.
| Total Sample (n = 6247) | |
|---|---|
| n (%) | |
| Sex (girls) | 3034 (48.6) |
| Age (years old) group | |
| <10 | 1291 (20.7) |
| 10–11 | 1167 (18.7) |
| 11–12 | 1351 (21.6) |
| 12–13 | 1146 (18.3) |
| >13 | 1292 (20.7) |
| School grade | |
| 4 | 1279 (20.5) |
| 5 | 1326 (21.2) |
| 6 | 1310 (21.0) |
| 7 | 1169 (18.7) |
| 8 | 1163 (18.6) |
| Father with university degree | 1666 (27.4) |
| Mother with university degree | 1339 (22.0) |
| Lives with a sibling | 1513 (25.0) |
| Self-reported academic pressure | |
| Not at all or seldom | 958 (16.7) |
| A little | 2738 (47.8) |
| Yes or very much | 2036 (35.5) |
| Daily screen time ≥ 2 hours | 686 (12.4) |
| Overweight/obese a | 2382 (40.1) |
a According to International Task Force on Obesity Asian reference, sex-age-specific BMI cut-offs that correspond to overweight BMI of 23kg/m2 at age 18 years.