Table 4. Repeat cross-sectional associations between exposure to a motorway and change in SF-8 physical and mental component score.
| Beta coefficient (95% CI) | ||||||
|---|---|---|---|---|---|---|
| Exposure | Outcome: SF-8 physical component score | |||||
| obs | Model 1 | obs | Model 2 | obs | Model 3 | |
| Area: East (reference: North) | 1895 | 0.1 (-2.6, 2.7) | 1870 | -0.5 (-2.9, 1.9) | 1778 | -0.8 (-2.6, 1.0) |
| Proximity within East study area | 634 | 2.1 (-1.0, 5.2) | 628 | 0.7 (-2.0, 3.4) | 591 | 1.5 (-0.7, 3.6) |
| Area: South (reference: North) | 1895 | 1.0 (-1.7, 3.6) | 1870 | 0.2 (-2.2, 2.6) | 1778 | -0.2 (-2.0, 1.7) |
| Proximity within South study area | 604 | -6.0 (-10.6, -1.5)* | 593 | -5.2 (-9.4, -0.9)* | 571 | -1.5 (-4.8, 1.7) |
| Outcome: SF-8 mental component score | ||||||
| obs | Model 1 | obs | Model 2 | obs | Model 3 | |
| Area: East (reference: North) | 1895 | 0.0 (-2.6, 2.6) | 1870 | -0.1 (-2.7, 2.5) | 1778 | 0.5 (-1.8, 2.8) |
| Proximity within East study area | 634 | -1.3 (-4.5, 1.9) | 628 | -1.6 (-4.9, 1.6) | 591 | -0.7 (3.5, 2.1) |
| Area: South (reference: North) | 1895 | -0.6 (-3.2, 2.0) | 1870 | -0.6 (-3.3, 2.0) | 1778 | -0.8 (-3.1, 1.5) |
| Proximity within South study area | 604 | -3.3 (-7.8, 1.1) | 593 | -3.7 (-8.2, 0.8) | 571 | 1.4 (-2.6, 5.4) |
CI–confidence interval; obs–observations
*p<0.05
**p<0.01
***p<0.001
Model 1 is unadjusted. Model 2 is adjusted for age and sex. Model 3 is adjusted for variables in model 2 plus home ownership, car ownership, working status, perceived financial strain, presence of a chronic condition and years lived in the local area. North–study area containing no motorway infrastructure; East–study area containing existing M8 motorway; South–study area containing new M74 motorway. Proximity refers to the distance from each participant’s home address in a straight line to the nearest motorway infrastructure