Table 2 Characteristics of the longitudinal sample with matched data at both Waves
Characteristics at baseline (n = 7,054) | |
|---|---|
Socio-demographic characteristics | |
Age (years) mean (SD) | 12.3 (2.4) |
Female n (%) | 3,477 (49.3) |
Secondary school n (%) | 3,969 (56.3) |
Urban n (%) | 4,402 (62.4) |
GDP n (%) | |
Low | 2,361 (33.5) |
Medium | 2,277 (32.3) |
High | 2,416 (34.3) |
Normal weighta n (%) | 5,686 (80.6) |
Primary outcomes | |
Total sedentary behaviour time (minutes/day), median (IQR) | 330 (240) |
Electronic device use time (minutes/day), median (IQR) | 60 (125) |
Homework time (hours/day), n (%) | |
0 h | 50 (0.8) |
< 1 h | 1,366 (20.9) |
1–2 h | 2,709 (41.4) |
2–3 h | 1,449 (22.2) |
≥ 3 h | 966 (14.8) |
Out-of-campus learning time (hours/day), n (%) | |
0 h | 4,291 (63.7) |
< 1 h | 484 (7.2) |
1–2 h | 767 (11.4) |
2–3 h | 527 (7.8) |
≥ 3 h | 672 (10) |
Secondary outcomes | |
Total screen viewing time (minutes/day), median (IQR) | 150 (192) |
Internet use time (minutes/day), median (IQR) | 90 (150) |
Meeting screen-viewing time recommendation‡, n (%) | 2,499 (35.6) |
Meeting regulatory requirement on homework time§, n (%) | 2,693 (41.2) |