Table 2.
Multilevel linear regression models of the associations between availability of major chain fast-food outlets at baseline and body mass index from wave I to wave III (n=882)
| Variable | Model 1 | Model 2 | Model 3 |
| Major chain fast-food outlets within 2 km Coefficient (95% CI) |
Major chain fast-food outlets within 3 km Coefficient (95% CI) |
Major chain fast-food outlets within 5 km Coefficient (95% CI) |
|
| Intercept | 26.68 (25.71 to 27.65)*** | 26.88 (25.89 to 27.88)*** | 27.27 (26.32 to 28.21)*** |
| Time (years) | 0.17 (0.13 to 0.22)*** | 0.17 (0.12 to 0.21)*** | 0.16 (0.11 to 0.21)*** |
| Fast-food availability exposure | |||
| Number of outlets | −0.06 (−0.21 to 0.10) | −0.06 (−0.13 to 0.02) | −0.05 (−0.07 to –0.03)*** |
| Number of outlets and time interaction | −0.001 (−0.011 to 0.010) | 0.001 (−0.004 to 0.006) | 0.001 (−0.001 to 0.003) |
| Potential confounders† | |||
| Age at baseline‡ | 0.08 (0.03 to 0.14)** | 0.08 (0.03 to 0.14)** | 0.08 (0.03 to 0.14)** |
| Education | |||
| Medium | −0.36 (−0.98 to 0.27) | −0.35 (−0.97 to 0.28) | −0.32 (−0.95 to 0.31) |
| High | −0.96 (−1.76 to –0.15)* | −0.94 (−1.74 to –0.14)* | −0.88 (−1.69 to –0.07)* |
| Employment | |||
| Part-time | −0.22 (−0.51 to 0.08) | −0.22 (−0.51 to 0.08) | −0.22 (−0.51 to 0.08) |
| Not in employment | −0.06 (−0.42 to 0.30) | −0.06 (−0.42 to 0.30) | −0.06 (−0.42 to 0.31) |
| Household income | |||
| $500 to <$1000 | −0.12 (−0.61 to 0.37) | −0.12 (−0.62 to 0.37) | −0.13 (−0.62 to 0.37) |
| $1000 to <$1500 | −0.04 (−0.53 to 0.44) | −0.04 (−0.52 to 0.44) | −0.04 (−0.52 to 0.44) |
| $1500+ | −0.04 (−0.57 to 0.49) | −0.03 (−0.56 to 0.50) | −0.02 (−0.55 to 0.51) |
| Children in household | |||
| No | −0.23 (−0.66 to 0.21) | −0.21 (−0.65 to 0.22) | −0.20 (−0.64 to 0.24) |
| Urban | |||
| Rural | 0.34 (−0.52 to 1.20) | 0.15 (−0.75 to 1.04) | −0.26 (−1.13 to 0.62) |
| Variance | Variance | Variance | |
| Intercept | 34.58 (29.81 to 40.11) | 34.52 (29.74 to 40.06) | 34.34 (29.57 to 39.89) |
| Slope | 0.12 (0.08 to 0.17) | 0.12 (0.08 to 0.17) | 0.12 (0.08 to 0.17) |
| Residual | 2.17 (1.74 to 2.71) | 2.17 (1.74 to 2.71) | 2.17 (1.74 to 2.71) |
| Covariance | Covariance | Covariance | |
| Intercept, slope§ | 0.19 (−0.13 to 0.67) | 0.19 (−0.13 to 0.68) | 0.19 (−0.12 to 0.68) |
†Reference categories: low education, full-time employment, <$500, yes children in household, urban.
‡Age was centred at 37 years.
§Considers covariance between these random components.
*p<0.05; **p<0.01; ***p<0.001.