Table 1 Demographic characteristics and potential overweight/obesity influencing factors of participants of different genders at different educational stages
Primary school | χ2 (p) / F (p) | Middle school | χ2 (p) / F (p) | High school | χ2 (p) / F (p) | χ2 (p) / F (p) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Overall n (%) | Male n (%) | Female n (%) | Overall n (%) | Male n (%) | Female n (%) | Overall n (%) | Male n (%) | Female n (%) | ||||||
Age | 10.17 ± 0.61 | 10.17 ± 0.62 | 10.16 ± 0.60 | 0.93 | 13.18 ± 0.92 | 13.22 ± 0.96 | 13.14 ± 0.86 | 1.29 | 16.27 ± 0.66 | 16.27 ± 0.70 | 16.28 ± 0.63 | −0.22 | 68,865.33 *** | |
Height (cm) | 143.85 ± 7.87 | 144.13 ± 7.59 | 143.57 ± 8.14 | 2.33* | 161.72 ± 8.14 | 163.95 ± 8.44 | 159.04 ± 6.89 | 9.08*** | 168.22 ± 8.45 | 174.47 ± 6.32 | 162.78 ± 5.93 | 46.41*** | 7222.47 *** | |
Weight (kg) | 38.81 ± 9.73 | 40.42 ± 10.33 | 37.16 ± 8.78 | 11.13*** | 53.02 ± 12.01 | 54.53 ± 12.97 | 51.21 ± 10.47 | 4.01*** | 62.27 ± 14.13 | 69.22 ± 14.62 | 56.24 ± 10.45 | 25.09*** | 2820.37 *** | |
Body mass index (kg/m2) | Underweight | 229 (5.3) | 92 (4.2) | 137 (6.4) | 221.64*** | 65 (7.8) | 41 (9.0) | 24 (6.3) | 7.69 | 198 (8.4) | 71 (6.4) | 127 (10.0) | 94.39*** | 54.10 *** |
Normal | 2796 (65.0) | 1216 (55.9) | 1580 (74.3) | 563 (67.4) | 289 (63.4) | 274 (72.3) | 1538 (64.9) | 638 (57.9) | 900 (70.9) | |||||
Overweight | 667 (15.5) | 466 (21.4) | 201 (9.5) | 128 (15.3) | 79 (17.3) | 49 (12.9) | 400 (16.9) | 229 (20.8) | 171 (13.5) | |||||
Obese | 608 (14.1) | 400 (18.4) | 208 (9.8) | 79 (9.5) | 47 (10.3) | 32 (8.4) | 235 (9.9) | 164 (14.9) | 71 (5.6) | |||||
Indoor PA time (m/day)† | < 30 | 2034 (47.9) | 1013 (47.2) | 1021 (48.6) | 30.54*** | 435 (52.1) | 237 (52.4) | 198 (53.2) | 0.34 | 1642 (69.3) | 755 (68.9) | 887 (70.3) | 4.97* | 297.85 *** |
30–60 | 1383 (32.6) | 645 (30.1) | 738 (35.1) | 256 (30.7) | 139 (30.8) | 117 (31.5) | 480 (20.2) | 215 (19.6) | 265 (21.0) | |||||
> 60 | 829 (19.5) | 486 (22.7) | 343 (16.3) | 133 (15.9) | 76 (16.8) | 57 (15.3) | 235 (9.9) | 125 (11.4) | 110 (8.7) | |||||
Outdoor PA time (m/day) | < 30 | 910 (21.3) | 453 (21.0) | 457 (21.6) | 20.88*** | 125 (15.0) | 76 (16.7) | 49 (12.9) | 4.59 | 617 (26.0) | 259 (23.5) | 358 (28.3) | 9.24* | 184.77*** |
30–60 | 1637 (38.2) | 764 (35.3) | 873 (41.2) | 312 (37.4) | 177 (38.8) | 135 (35.6) | 1125 (47.4) | 526 (47.8) | 599 (47.3) | |||||
> 60 | 1734 (40.5) | 945 (43.7) | 789 (37.2) | 398 (47.7) | 203 (44.5) | 195 (51.5) | 625 (26.4) | 316 (28.7) | 309 (24.4) | |||||
Sedentary time (h/day) | < 2 | 925 (21.7) | 498 (23.1) | 427 (20.2) | 10.25* | 91 (10.9) | 60 (13.2) | 31 (8.2) | 14.63** | 86 (3.6) | 59 (5.4) | 27 (2.1) | 33.83*** | 1507.97 *** |
2–4 | 1190 (27.7) | 569 (26.4) | 621 (29.4) | 223 (26.7) | 132 (29.0) | 91 (24.0) | 236 (10.0) | 128 (11.6) | 108 (8.5) | |||||
4–6 | 1013 (23.6) | 501 (23.2) | 512 (24.2) | 188 (22.5) | 101 (22.2) | 87 (23.0) | 391 (16.5) | 200 (18.2) | 191 (15.1) | |||||
6–8 | 705 (16.4) | 352 (16.3) | 353 (16.7) | 159 (19.0) | 86 (18.9) | 73 (19.3) | 573 (24.2) | 240 (21.8) | 333 (26.3) | |||||
> 8 | 435 (10.1) | 235 (10.9) | 200 (9.5) | 173 (20.7) | 76 (16.7) | 97 (25.6) | 1080 (45.6) | 474 (43.1) | 606 (47.9) | |||||
Academic stressa | 2.50 ± 1.04 | 2.56 ± 1.08 | 2.43 ± 0.99 | 4.04*** | 2.90 ± 0.86 | 2.97 ± 0.88 | 2.80 ± 0.81 | 2.90** | 3.27 ± 0.91 | 3.32 ± 1.02 | 3.22 ± 0.80 | 2.72** | 495.89 *** | |
Mental healthb | Poor | 550 (13.0) | 298 (13.9) | 252 (12.0) | 3.66 | 182 (21.8) | 110 (24.3) | 72 (19.1) | 3.29 | 848 (35.8) | 372 (34.0) | 476 (37.7) | 3.56 | 480.73 *** |
Good | 3694 (87.0) | 1840 (86.1) | 1854 (88.0) | 647 (77.5) | 342 (75.7) | 305 (80.9) | 1507 (63.6) | 722 (66.0) | 785 (62.3) | |||||
Smartphone screen time (h/day) | 0.61 ± 0.88 | 0.62 ± 0.93 | 0.60 ± 0.82 | 0.51 | 1.73 ± 1.72 | 1.78 ± 1.82 | 1.66 ± 1.59 | 1.02 | 1.98 ± 1.59 | 1.85 ± 1.56 | 2.09 ± 1.60 | −3.68*** | 855.60 *** | |
Non-smartphonescreen time (h/day) | 1.12 ± 1.74 | 1.26 ± 1.92 | 0.97 ± 1.51 | 5.56*** | 1.35 ± 2.17 | 1.58 ± 2.32 | 1.07 ± 1.94 | 3.30** | 0.79 ± 1.49 | 1.02 ± 1.91 | 0.58 ± 0.95 | 6.96*** | 43.23 *** | |
PSU for social network (out of 30 points) ‡,c | 8.01 ± 3.63 | 8.33 ± 4.03 | 7.68 ± 3.14 | 5.86*** | 10.65 ± 4.56 | 11.03 ± 4.92 | 10.18 ± 4.05 | 2.69** | 12.97 ± 5.14 | 12.91 ± 5.45 | 13.01 ± 4.86 | −0.49 | 908.61 *** | |
PSU for entertainment (out of 20 points) | 7.56 ± 4.24 | 8.36 ± 4.61 | 6.74 ± 3.66 | 12.68*** | 9.85 ± 4.48 | 11.26 ± 4.43 | 8.15 ± 3.91 | 10.66*** | 10.77 ± 4.40 | 12.20 ± 4.38 | 9.54 ± 4.03 | 15.38*** | 444.86*** | |
PSU for information collection (out of 15 points) | 5.42 ± 3.06 | 5.67 ± 3.26 | 5.16 ± 2.81 | 5.42*** | 5.79 ± 2.80 | 6.02 ± 2.91 | 5.53 ± 2.64 | 2.49* | 5.79 ± 2.73 | 6.00 ± 2.92 | 5.61 ± 2.54 | 3.40** | 15.45*** | |
Total score of PSU (out of 65 points) | 20.95 ± 8.66 | 22.32 ± 9.43 | 19.54 ± 7.55 | 10.63*** | 26.24 ± 9.21 | 28.24 ± 9.47 | 23.83 ± 8.30 | 7.09*** | 29.52 ± 9.35 | 31.09 ± 9.87 | 28.16 ± 8.64 | 7.69*** | 703.51*** | |