Table 1 Basic characteristics of participants (N = 22612)
Characteristics | All (N = 22612) | Boys (N = 9375) | Girls (N = 13237) | Test statistics |
|---|---|---|---|---|
Age (years, mean, SD) | 14.7 (1.70) | 14.6 (1.70) | 14.7 (1.70) | t = -3.35, p = 0.019 |
Form (%) | χ2 = 27.52, p < 0.001 | |||
Junior (F1–F3)a | 59.6 | 61.7 | 58.2 | |
Senior (F4–F7)a | 40.4 | 38.3 | 41.8 | |
BMI (kg/m2, mean, SD) | 19.2 (2.99) | 19.5 (3.29) | 18.9 (2.73) | t = 13.29, p < 0.001 |
Weight status by local references (%) | χ2 = 204.15, p < 0.001 | |||
Underweight | 8.7 | 8.6 | 8.7 | |
Normal weight | 79.0 | 75.3 | 81.6 | |
Overweight/Obese | 12.4 | 16.1 | 9.7 | |
Parental education level (%) | χ2 = 26.07, p < 0.001 | |||
Primary or below | 12.0 | 12.2 | 11.9 | |
Secondary | 65.9 | 64.1 | 67.2 | |
Tertiary or above | 22.1 | 23.7 | 21.0 | |
Place of birth (%) | χ2 = 3.63, p = 0.06 | |||
Hong Kong | 73.9 | 73.6 | 74.6 | |
Other placesb | 26.1 | 26.4 | 25.4 | |
Family affluence (%) | χ2 = 38.03, p < 0.001 | |||
Relatively poor | 36.4 | 38.6 | 34.9 | |
Medium | 52.6 | 50.3 | 54.3 | |
Relatively wealthy | 10.9 | 11.1 | 10.8 | |
Weight perception (%) | χ2 = 177.35, p < 0.001 | |||
Correct perception | 47.6 | 52.9 | 43.9 | |
Weight misperception | 52.4 | 47.1 | 56.1 | |
Received weight comments of being "too fat" | 29.0 | 22.3 | 33.8 | χ2 = 350.00, p < 0.001 |
Received weight comments of being "too thin" | 26.9 | 28.4 | 25.8 | χ2 = 17.71, p < 0.001 |