Table 3. Odds Ratio by Exposure Variable.
| Odds Ratio | Adjusted Odds Ratio* | |
|---|---|---|
| Driving Speed (mph) | ||
| >20 | 2.09, 95% CI (1.79, 2.42) | 2.02, 95% CI (1.73, 2.36) |
| ≤20 | Reference | |
| Posted Speed (mph) | ||
| >30 | 1.52, 95% CI (1.33, 1.74) | 1.40, 95% CI (1.22, 1.62) |
| ≤30 | Reference | |
| Protective Equipment | ||
| Safety Helmet | 0.95, 95% CI (0.79, 1.14) | 0.86, 95% CI (0.72, 1.04) |
| Eye Protection | 1.38, 95% CI (0.82, 2.33) | 1.29, 95% CI (0.76, 2.19) |
| No Protection | Reference | |
| Alcohol/ Drug Use | ||
| Yes | 2.29, 95% CI (1.81, 2.90) | 2.09, 95% CI (1.64, 2.66) |
| No | Reference | |
| Time of Day | ||
| 6:01am- 4:00pm | 0.95, 95% CI (0.80, 1.13) | 0.90, 95% CI (0.76, 1.08) |
| 7:01pm- 6:00am | 1.19, 95% CI (1.00, 1.42) | 1.19, 95% CI (0.99, 1.44) |
| 4:01pm- 7:00pm | Reference | |
| Day of the week | ||
| Monday | 1.01, 95% CI (0.78, 1.30) | 0.93, 95% CI (0.71, 1.21) |
| Tuesday | 1.09 , 95% CI (0.84, 1.41) | 1.05, 95% CI (0.81, 1.37) |
| Wednesday | 0.94, 95% CI (0.72, 1.22) | 0.93, 95% CI (0.71, 1.22) |
| Thursday | 1.04, 95% CI (0.81, 1.33) | 1.02, 95% CI (0.79, 1.32) |
| Friday | 0.91, 95% CI (0.71, 1.17) | 0.86, 95% CI (0.66, 1.44) |
| Saturday | 1.02, 95% CI (0.80, 1.30) | 1.01, 95% CI (0.78, 1.30) |
| Sunday | Reference | |
| Lighting conditions | ||
| Dark (no light) | 1.69, 95% CI (1.23, 2.31) | 1.69, 95% CI (1.23, 2.32) |
| Dark (street light) | 1.22, 95% CI (1.04, 1.43) | 1.29, 95% CI (1.09, 1.53) |
| Dusk | 0.84, 95% CI (0.57, 1.24) | 0.98, 95% CI (0.66, 1.44) |
| Dawn | 0.82, 95% CI (0.39, 1.75) | 0.95, 95% CI (0.44, 2.04) |
| Daylight | Reference | |
| Weather | ||
| Cloudy | 1.21, 95% CI (1.00, 1.47) | 1.25, 95% CI (1.02, 1.52) |
| Rainy | 0.76, 95% CI (0.54, 1.08) | 0.75, 95% CI (0.52, 1.08) |
| Foggy | 1.03, 95% CI (0.22, 4.76) | 0.97, 95% CI (0.21, 4.49) |
| Clear | Reference | |
| Town Classification | ||
| College | 0.54, 95% CI (0.35, 0.83) | 0.64, 95% CI (0.41, 1.00) |
| University Associated | 1.05, 95% CI (0.89, 1.23) | 1.05, 95% CI (0.89, 1.24) |
| Other | Reference | |
| County Location | ||
| Coastal | 1.07, 95% CI (0.86, 1.33) | 1.01, 95% CI (0.80, 1.26) |
| Non-coastal | Reference | |
| Roadway | ||
| Off-roadway | 1.04, 95% CI (0.86, 1.26) | 0.96, 95% CI (0.79, 1.17) |
| On-roadway | Reference | |
| Road surface type | ||
| Slag/ Gravel/ Stone | 0.91, 95% CI (0.64, 1.29) | 0.88, 95% CI (0.61, 1.25) |
| Brick/ Block | 0.16, 95% CI (0.02, 1.19) | 0.24, 95% CI (0.03, 1.79) |
| Concrete | 0.85, 95% CI (0.59, 1.24) | 0.90, 95% CI (0.61, 1.33) |
| Dirt | 1.30, 95% CI (0.70, 2.43) | 1.51, 95% CI (0.80, 2.87) |
| Blacktop | Reference | |
| Road surface condition | ||
| Wet | 0.82, 95% CI (0.63, 1.29) | 0.88, 95% CI (0.62, 1.07) |
| Slippery | 0.88, 95% CI (0.41, 1.87) | 0.84, 95% CI (0.39, 1.81) |
| Icy | 4.48, 95% CI (0.28, 71.73) | 4.28, 95% CI (0.27, 69.05) |
| Dry | Reference | |
| Type of Shoulder | ||
| Curb | 1.22, 95% CI (1.04, 1.45) | 1.22, 95% CI (1.02, 1.44) |
| Unpaved | 1.57, 95% CI (1.32, 1.88) | 1.57, 95% CI (1.30, 1.88) |
| Paved | Reference | |
| Highway type | ||
| Divided | 1.25, 95% CI (1.08,1.44) | 1.21, 95% CI (1.04, 1.40) |
| Undivided | Reference | |
| Number of Lanes | ||
| 0 | 0.98, 95% CI (0.55, 1.76) | 1.00, 95% CI (0.55, 1.84) |
| 2 | 1.71, 95% CI (1.01, 2.91) | 1.62, 95% CI (0.93, 2.82) |
| 3 | 1.64, 95% CI (0.88, 3.07) | 1.52, 95% CI (0.80, 2.92) |
| 4 | 2.06, 95% CI (1.20, 3.52) | 1.83, 95% CI (1.04, 3.21) |
| 5 | 1.92, 95% CI (0.99, 3.72) | 1.53, 95% CI (0.76, 3.07) |
| 6 | 2.43, 95% CI (1.39, 4.23) | 2.11, 95% CI (1.18, 3.77) |
| 7 | 1.70, 95% CI (0.65, 4.46) | 1.44, 95% CI (0.67, 5.02) |
| 8 | 2.00, 95% CI (0.75, 5.32) | 1.83, 95% CI (0.67, 5.02) |
| ≥9 | 11.96, 95% CI (3.05, 46.95 ) | 10.06, 95% CI (2.51, 40.27) |
| 1 | Reference |
*
Adjusted by age, gender, and insurance status