Table 2. Time-varying factors of study subjects.
| 2.5 years old | 4.5 years old | 7 years old | 10 years old | 13 years old | |||
| Boys | Number | 18,013 | 18,463 | 16,223 | 16,119 | 14,911 | |
| Overweight/Obese | No | 16,581 (92.1%) | 17,302 (93.7%) | 14,723 (90.8%) | 14,053 (87.2%) | 13,410 (89.9%) | |
| Yes | 1,432 (7.9%) | 1,161 (6.3%) | 1,500 (9.2%) | 2,066 (12.8%) | 1,501 (10.1%) | ||
| Skipping breakfast | No | 16,029 (89.0%) | 14,944 (80.9%) | 15,672 (96.6%) | 15,981 (99.1%) | 13,854 (92.9%) | |
| Yes | 1,984 (11.0%) | 3,519 (19.1%) | 551 (3.4%) | 138 (0.9%) | 1,057 (7.1%) | ||
| Living with a grandparent | No | 13,952 (77.5%) | 14,203 (76.9%) | 12,319 (75.9%) | 12,402 (76.9%) | 11,688 (78.4%) | |
| Yes | 4,061 (22.5%) | 4,260 (23.1%) | 3,904 (24.1%) | 3,717 (23.1%) | 3,223 (21.6%) | ||
| Watching television (hours per day) | <1 | 1,859 (10.3%) | 2,005 (10.9%) | 4,450 (27.4%) | 3,134 (19.4%) | — | |
| 1–<2 | 6,638 (36.9%) | 5,446 (29.5%) | 7,412 (45.7%) | 6,998 (43.4%) | — | ||
| 2–<3 | 2,536 (14.1%) | 6,568 (35.6%) | 3,346 (20.6%) | 4,197 (26.0%) | — | ||
| ≥3 | 6,600 (36.6%) | 4,255 (23.0%) | 987 (6.1%) | 1,731 (10.7%) | — | ||
| Missing | 380 (2.1%) | 189 (1.0%) | 28 (0.2%) | 59 (0.4%) | — | ||
| Playing computer games (hours per day) | <1 | — | 16,578 (89.8%) | 12,749 (78.6%) | 10,986 (68.0%) | — | |
| 1–<2 | — | 1,464 (7.9%) | 2,902 (17.9%) | 4,176 (25.9%) | — | ||
| ≥2 | — | 379 (2.1%) | 480 (3.0%) | 863 (5.4%) | — | ||
| Missing | — | 42 (0.2%) | 92 (0.6%) | 112 (0.7%) | — | ||
| Girls | Number | 16,636 | 17,009 | 15,043 | 15,092 | 13,861 | |
| Overweight/Obese | No | 14,969 (90.0%) | 15,458 (90.9%) | 13,657 (90.8%) | 13,778 (91.3%) | 13,063 (94.2%) | |
| Yes | 1,667 (10.0%) | 1,551 (9.1%) | 1,386 (9.2%) | 1,314 (8.7%) | 798 (5.8%) | ||
| Skipping breakfast | No | 14,599 (87.8%) | 13,697 (80.5%) | 14,547 (96.7%) | 14,967 (99.2%) | 12,872 (92.9%) | |
| Yes | 2,037 (12.2%) | 3,312 (19.5%) | 496 (3.3%) | 125 (0.8%) | 989 (7.1%) | ||
| Living with a grandparent | No | 12,907 (77.6%) | 13,081 (76.9%) | 11,498 (76.4%) | 11,714 (77.6%) | 10,912 (78.7%) | |
| Yes | 3,729 (22.4%) | 3,928 (23.1%) | 3,545 (23.6%) | 3,378 (22.4%) | 2,949 (21.3%) | ||
| Watching television (hours per day) | <1 | 1,692 (10.2%) | 2,139 (12.6%) | 4,450 (29.6%) | 3,053 (20.2%) | — | |
| 1–<2 | 6,140 (36.9%) | 5,162 (30.3%) | 6,621 (44.0%) | 6,254 (41.4%) | — | ||
| 2–<3 | 2,340 (14.1%) | 5,815 (34.2%) | 3,025 (20.1%) | 4,000 (26.5%) | — | ||
| ≥3 | 6,147 (36.9%) | 3,721 (21.9%) | 923 (6.1%) | 1,742 (11.5%) | — | ||
| Missing | 317 (1.9%) | 172 (1.0%) | 24 (0.2%) | 43 (0.3%) | — | ||
| Playing computer games (hours per day) | <1 | — | 16,346 (96.1%) | 13,816 (91.8%) | 13,255 (87.8%) | — | |
| 1–<2 | — | 528 (3.1%) | 1,022 (6.8%) | 1,578 (10.5%) | — | ||
| ≥2 | — | 112 (0.7%) | 93 (0.6%) | 179 (1.2%) | — | ||
| Missing | — | 23 (0.1%) | 112 (0.7%) | 80 (0.5%) | — | ||