Table 4.
Matched and un-matched logistic regression estimates of the association between environment risk factors and severe bicyclist injury.
| Matched OR | 95% CI | Adjustment factors | Un-matched OR | 95% CI | Adjustment factors | |
|---|---|---|---|---|---|---|
| Traffic volume | ||||||
| Lowa | 1 | Reference | 1 | Reference | ||
| Meda | 3.20 | 0.63, 16.25 | Riding fast | 1.22 | 0.37, 4.01 | Age |
| Higha | 2.01 | 0.51, 7.94 | Riding fast | 1.53 | 0.61, 3.85 | Age |
| Avg. traffic speed (>30 km/hr) | 1.7 | 0, 3.91 | b | 4.13 | 0.89, 19.11 | Speed and riding fast |
| High speed limit (>30 km/hr) | 1.85 | 0.46, 7.47 | b | 1.14 | 0.41, 3.21 | b |
|
| ||||||
| Land use | ||||||
| Retail | 8.12* | 1.66, 39.7 | b | 2.53* | 1.10, 5.83 | Age |
| School | 0.24 | 0.03, 1.05 | b | 0.35 | 0.04, 2.84 | Age and speed |
| Nature | 0.41 | 0.14, 1.24 | Age | 1.25 | 0.60, 2.57 | b |
|
| ||||||
| Path characteristics (side 1) | ||||||
| Type of path | ||||||
| Sidewalk | 1 | Reference | 1 | Reference | ||
| No path | 1.29 | 0.24, 6.81 | Riding fast | 1.10 | 0.30, 4.02 | b |
| Multi-use path# | 0.24* | 0.08, 0.77 | Riding fast | 1.30 | 0.59, 2.87 | b |
| Path location (distance from road) | ||||||
| Within 1 m of road | 1 | Reference | 1 | Reference | ||
| Btw 1 and 3 m of road | 0.54 | 0.14, 2.09 | Age | 1.68 | 0.59, 4.81 | Speed |
| >3 m from road | 0.48 | 0.16, 1.45 | Age | 1.42 | 0.52, 3.85 | Speed |
| Sloped path | 0.42 | 0, 1.63 | b | 1.83 | 0.71, 4.76 | Speed |
| Path obstructions | 0.36 | 0.13, 1.01 | Age | 0.81 | 0.38, 1.74 | b |
|
| ||||||
| Path characteristics (side 2) | ||||||
| Type of path | ||||||
| Sidewalk | 1 | Reference | 1 | Reference | ||
| No path | 1.14 | 0.36, 3.62 | Age | 0.86 | 0.28, 2.65 | Age and speed |
| Multi-use path# | 0.40 | 0.10, 1.68 | Age | 2.12 | 0.73, 6.21 | Age and speed |
| Path location (distance from road) | ||||||
| Within 1 m | 1 | Reference | 1 | Reference | ||
| Btw 1 and 3 m | 0.11 | 0.01, 1.64 | Age | 0.96 | 0.28, 3.31 | Speed |
| >3 m | 0.36 | 0.06, 2.06 | Age | 1.95 | 0.59, 6.49 | Speed |
| Sloped path | 1.11 | 0.23, 5.32 | b | 1.93 | 0.65, 5.75 | b |
| Path obstructions | 3.32 | 0.65, 16.9 | b | 1.10 | 0.45, 2.73 | b |
|
| ||||||
| Roadway characteristics | ||||||
| Good road condition | 0.25* | 0.07, 0.96 | b | 0.43* | 0.19, 0.96 | b |
| >4 lanes of traffic | 2.59 | 0.80, 8.4 | b | 2.31 | 0.87, 6.16 | Age, speed, and riding fast |
| Curb | ||||||
| Mountable | 1 | Reference | 1 | Reference | ||
| Non-mountable | 4.51* | 1.08, 18.8 | Sex | 1.62 | 0.71, 3.71 | b |
| No curb | 0.34 | 0.04, 3.17 | Sex | 0.44 | 0.05, 3.53 | b |
| Crossings | 1.1 | 0.39, 3.15 | b | 1.85 | 0.75, 4.58 | Speed |
| Other routes | 0.44 | 0.16, 1.16 | Riding fast | 0.75 | 0.34, 1.68 | Speed |
|
| ||||||
| Safety characteristics | ||||||
| Street lights (side 1) | 1.90 | 0.70, 5.12 | Age | 0.78 | 0.34, 1.79 | Speed |
| Street lights (side 2) | 0.89 | 0.29, 2.77 | b | 0.38* | 0.15, 0.97 | Age and speed |
| Lighting over path (side 1) | 0.36 | 0.07, 1.86 | b | 0.43 | 0.15, 1.22 | Sex |
| Lighting over path (side 2) | 0.58 | 0.16, 2.15 | b | 0.39 | 0.15, 1.04 | Sex |
| High surveillance | 0.53 | 0.17, 1.71 | b | 0.32* | 0.13, 0.82 | Speed |
| Aesthetic characteristics | ||||||
| >1 tree/block (side 1) | 2.19 | 0.41, 11.78 | b | 2.07 | 0.57, 7.53 | Speed |
| >1 tree/block (side 2) | 1.98 | 0.22, 17.88 | b | 1.75 | 0.48, 6.42 | Speed |
| Clean | 1.79 | 0.59, 5.43 | Age | 1.52 | 0.60, 3.85 | b |
| Attractive for bicycling | 0.4 | 0.13, 1.23 | b | 0.49 | 0.18, 1.32 | Age and speed |
| Continuity of path | 3.0 | 0.35, 25.96 | b | 2.34 | 0.29, 19.04 | Age, speed, and riding fast |
MV: motor vehicle; OR: odds ratio; CI: confidence interval.
*Represents significance based on CI not including the null value.
aLow volume: ≤250 vehicles/hr, medium volume: 250–749 vehicles/hr, high volume: ≥750 vehicles/hr.
bIf model could not accommodate the addition of one or more covariates, the crude estimate was retained.