Table 1.
Descriptive statistics of participants by age groups
| Characteristics | Total (N = 7555) |
Age 6–8 (N = 1925) |
Age 9–11 (N = 2535) |
Age 12–17 (N = 3095) |
P-value |
|---|---|---|---|---|---|
| Age, mean (SD) | 11.5 (3.2) | 7.7 (0.7) | 10.5 (0.8) | 14.8 (1.7) | < 0.001* |
| Gender, % (n) | < 0.001* | ||||
| Female | 55.1% (4166) | 52.1% (1003) | 52.3% (1325) | 59.4% (1838) | |
| Male | 44.9% (3389) | 47.9% (922) | 47.7% (1210) | 40.6% (1257) | |
| EQ-VAS, mean (SD) | 82.7 (18.5) | 88.9 (18.7) | 85.2 (17.6) | 77.1 (17.5) | < 0.001* |
| PedsQL, mean (SD) | |||||
| Physical functioning | 85.1 (14.1) | 86.1 (15.5) | 88.1 (12.5) | 82.2 (13.8) | < 0.001* |
| Emotional functioning | 72.9 (19.9) | 76.3 (20.7) | 75.6 (19.2) | 68.7 (19.2) | < 0.001* |
| Social functioning | 84.4 (17.0) | 85.2 (18.3) | 86.8 (16.0) | 82.0 (16.6) | < 0.001* |
| School functioning | 78.4 (16.5) | 80.9 (17.4) | 82.2 (14.9) | 73.7 (16.0) | < 0.001* |
| Psychosocial health summary score | 78.6 (14.9) | 80.8 (15.7) | 81.5 (13.9) | 74.8 (14.3) | < 0.001* |
| Physical health summary score | 85.1 (14.1) | 86.1 (15.5) | 88.1 (12.5) | 82.2 (13.8) | < 0.001* |
| Total score | 80.9 (13.4) | 82.6 (14.3) | 83.8 (12.3) | 77.4 (12.8) | < 0.001* |
| IPAQ, mean (SD) | |||||
| Sedentary activities, min per day | 312.7 (223.0) | 224.5 (483.3) | 287.9 (354.4) | 388.0 (320.0) | < 0.001* |
| Walking, min per day | 73.3 (72.3) | 60.3 (137.7) | 82.1 (140.6) | 74.2 (105.4) | < 0.001* |
| Moderate activities, min per day | 41.4 (42.5) | 37.2 (120.8) | 45.9 (87.5) | 40.3 (95.5) | 0.002* |
| Vigorous activities, min per day | 32.3 (36.6) | 24.9 (120.4) | 35.5 (77.8) | 34.3 (80.0) | < 0.001* |
| Total physical MET score | 4662.4 (3325.9) | 3827.3 (8459.6) | 5173.3 (7278.7) | 4764.0 (6906.3) | < 0.001* |
| IPAQ Physical level, % (n) | < 0.001* | ||||
| Low | 2.6% (198) | 4.0% (76) | 2.7% (52) | 1.7% (33) | |
| Moderate | 29.9% (2261) | 38.0% (962) | 26.0% (658) | 28.2% (715) | |
| High | 67.4% (5096) | 58.1% (1796) | 71.4% (2207) | 70.1% (2168) | |
| Use of electronic devices, hours per day, mean (SD) | |||||
| Weekdays | |||||
| Screen time for studying | 1.0 (1.2) | 0.7 (2.1) | 0.9 (2.1) | 1.3 (2.0) | < 0.001* |
| Screen time for gaming and leisure | 3.5 (3.4) | 2.3 (5.2) | 2.8 (5.3) | 4.8 (6.0) | < 0.001* |
| Total screen time | 4.5 (3.7) | 3.0 (6.2) | 3.7 (5.7) | 6.0 (6.2) | < 0.001* |
| Weekends | |||||
| Screen time for studying | 1.1 (1.3) | 0.8 (2.4) | 1.0 (2.4) | 1.3 (2.4) | < 0.001* |
| Screen time for gaming and leisure | 6.4 (4.3) | 5.1 (7.9) | 5.9 (8.3) | 7.6 (6.4) | < 0.001* |
| Total screen time | 7.5 (4.4) | 5.9 (8.6) | 6.9 (8.2) | 8.9 (6.4) | < 0.001* |
| Overall | |||||
| Screen time for studying | 1.0 (1.1) | 0.7 (2.0) | 0.9 (2.1) | 1.3 (2.0) | < 0.001* |
| Screen time for gaming and leisure | 4.3 (3.4) | 3.1 (5.6) | 3.7 (5.7) | 5.6 (5.7) | < 0.001* |
| Total screen time | 5.3 (3.6) | 3.9 (6.5) | 4.6 (5.9) | 6.8 (5.9) | < 0.001* |
| Sleeping duration, hours, mean (SD) | |||||
| Weekdays | 8.3 (1.4) | 9.1 (2.5) | 8.8 (1.7) | 7.5 (2.0) | < 0.001* |
| Weekends | 9.5 (1.5) | 9.9 (2.1) | 9.7 (2.8) | 9.0 (2.4) | < 0.001* |
| Overall | 8.6 (1.2) | 9.3 (2.0) | 9.0 (1.6) | 7.9 (1.8) | < 0.001* |
| Household monthly income, % (n) | < 0.001* | ||||
| < HK$12,000 | 14.5% (588) | 12.7% (138) | 15.4% (217) | 15.0% (233) | |
| HK$12,000–$19,999 | 25.2% (1021) | 23.5% (256) | 24.5% (344) | 27.1% (421) | |
| HK$20,000–$39,999 | 32.8% (1330) | 32.2% (351) | 29.6% (417) | 36.2% (562) | |
| ≥ HK$40,000 | 27.4% (1111) | 31.6% (344) | 30.5% (429) | 21.8% (338) | |
| Parental characteristics, % (n) | |||||
| Marital status | < 0.001* | ||||
| Married | 86.4% (3529) | 90.5% (994) | 87.5% (1241) | 82.6% (1294) | |
| Divorced/Separated | 11.9% (486) | 7.3% (80) | 11.1% (157) | 15.9% (249) | |
| Cohabitation | 1.7% (70) | 2.3% (25) | 1.5% (21) | 1.5% (24) | |
| Education level | |||||
| Mother | < 0.001* | ||||
| Primary school or below | 7.5% (310) | 3.6% (40) | 6.6% (94) | 11.1% (176) | |
| Secondary school | 70.2% (2899) | 65.0% (723) | 67.7% (968) | 76.0% (1208) | |
| Tertiary/University or above | 22.3% (921) | 31.4% (349) | 25.7% (367) | 12.9% (205) | |
| Father | < 0.001* | ||||
| Primary school or below | 5.9% (238) | 2.8% (31) | 4.7% (66) | 9.0% (141) | |
| Secondary school | 68.4% (2780) | 63.7% (695) | 65.4% (920) | 74.5% (1165) | |
| Tertiary/University or above | 25.7% (1044) | 33.5% (365) | 29.9% (421) | 16.5% (258) |
IPAQ, International Physical Activity Questionnaire; MET, Metabolic equivalent of task; SD, standard deviation
*Significant difference (p < 0.05) between groups by univariate linear regression, or multinomial logistic regression, as appropriate