Table 4.
Effects of household/family characteristics, school characteristics and adolescent’s characteristics on adolescent’s physical activity at school, and moderating effects of adolescent’s gender (Step 3 of mediation analysis)
| Household / family characteristics | Effect | PA at school during school hours | PA at school after school hours | ||
|---|---|---|---|---|---|
| b (95% CI) | p | eb (95% CI) | p | ||
| Highest educational attainment in household |
Main - direct In boys In girls |
1.57 (−0.48,3.62) 3.55 (0.83, 6.26) 0.11 (−2.38,2.60) |
0.134 0.010 0.931 |
1.08 (1.01,1.15) N/A N/A |
0.027 N/A N/A |
| No. of motor vehicles in household | Main - direct | 4.08 (0.63,7.54) | 0.021 | 1.11 (1.00,1.24) | 0.054 |
| In boys | 8.08 (2.72,13.44) | 0.003 | N/A | N/A | |
| In girls | 1.79 (− 2.36,5.94) | 0.398 | N/A | N/A | |
| No. of children in household | Main - direct | 2.24 (−0.91,5.39) | 0.164 | 1.09 (0.97,1.22) | 0.164 |
| Neighbourhood self-selection for PA | Main -direct | −1.76 (−4.83,1.31) | 0.262 | 0.94 (0.84,1.04) | 0.202 |
| Neighbourhood socio-economic status | Main - direct | 17.77 (9.27,26.27) | < 0.001 | 1.11 (0.91,1.37) | 0.305 |
| In boys | N/A | N/A | 1.33 (1.02,1.74) | 0.035 | |
| In girls | N/A | N/A | 0.97 (0.76,1.23) | 0.781 | |
| Household income | Main - direct | 1.15 (0.06,2.24) | 0.039 | 0.99 (0.96,1.03) | 0.601 |
| Parental rules for PA | Main - direct | 0.41 (−0.23,1.05) | 0.206 | 1.02 (1.00,1.04) | 0.040 |
| Social support for PA from parents | Main - direct | 1.04 (−1.84,3.91) | 0.479 | 1.05 (0.96,1.15) | 0.308 |
| In boys | 3.86 (− 0.03,7.74) | 0.052 | N/A | N/A | |
| In girls | −1.17 (−4.76,2.42) | 0.523 | N/A | N/A | |
| PA equipment at home / neighbourhood | Main - direct | 0.26 (−0.72,1.23) | 0.607 | 1.05 (1.02,.1.09) | 0.003 |
| Parental leisure-time PA^ | Main - direct | 0.62 (0.12,1.12) | 0.016 | 1.01 (1.00,1.03) | 0.083 |
| In boys | 1.87 (0.93,2.81) | < 0.001 | N/A | N/A | |
| In girls | 0.23 (− 0.35,0.81) | 0.438 | N/A | N/A | |
| Parental transportation PA^ | Main - direct | 0.22 (−0.24,0.69) | 0.351 | 1.01 (0.99,1.02) | 0.377 |
| In boys | 0.80 (0.11,1.49) | 0.023 | N/A | N/A | |
| In girls | −0.27 (− 0.89,0.35) | 0.392 | N/A | N/A | |
| School Characteristics | |||||
| School PA-friendly index‡ | Main - direct | 2.76 (1.19,4.33) | < 0.001 | 1.14 (1.08,1.20) | < 0.001 |
| Social support from peers | Main - direct | 2.82 (0.43,5.22) | 0.021 | 1.13 (1.04,1.22) | 0.003 |
| Adolescent’s characteristics | |||||
| Attitude towards PA | Main - direct | 11.13 (5.36,16.91) | < 0.001 | 2.05 (1.66,2.52) | < 0.001 |
| Enjoyment of PA | Main - direct | 4.48 (2.21, 6.75) | < 0.001 | 1.56 (1.43,1.69) | < 0.001 |
| Athletic ability | Main - direct | 5.04 (2.84,7.24) | < 0.001 | 1.78 (1.65,1.92) | < 0.001 |
PA = physical activity; b = regression coefficient; CI = confidence interval; eb = exponentiated regression coefficient; N/A denotes ‘no significant interaction’
^ minutes converted to hours (by dividing by 60); ‡ consisting of items measuring PA equipment at school and school PA-friendly policy supporting after-school PA. These regression models were adjusted for confounders listed in Table S3