Table 4. Prevalence and Likelihood of Occurrence of Driving Errors and Secondary Task Engagement During the First and Last Ten Hours of Practice Driving.
| Driving Errors | First 10 Hours N=90 participants# 9,823 observations | Last 10 hours N=79 participants# 8,523 observations | Odds Ratio (Last 10 Hours versus First 10 Hours) | ||||||
|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||
| N | Prevalence (St. Dev.)^ | N | Prevalence (St. Dev.)^ | Odds Ratio+ | 95% Confidence Interval | ||||
| Total Driving Errors | 1,13 8 | 13.4 | (19.4) | 786 | 8.8 | (13.0) | 0.76 | 0.68 | 0.84 |
| Performance Errors | 638 | 8.4 | (19.3) | 605 | 6.8 | (11.3) | 1.10 | 0.97 | 1.25 |
| Lane management | 400 | 4.8 | (7.4) | 578 | 6.4 | (11.3) | 1.72 | 1.49 | 1.98 |
| Loss of vehicle control | 3 | 0.0 | (0.2) | 0 | - | - | - | - | |
| Improper turning | 69 | 1.3 | (6.3) | 4 | 0.1 | (0.2) | 0.07 | 0.02 | 0.18 |
| Hard braking | 45 | 0.5 | (0.8) | 11 | 0.1 | (0.4) | 0.28 | 0.15 | 0.56 |
| Improper vehicle operation | 121 | 1.8 | (6.6) | 12 | 0.1 | (0.4) | 0.11 | 0.06 | 0.21 |
| Decision Errors | 352 | 3.5 | (2.9) | 124 | 1.4 | (2.4) | 0.40 | 0.32 | 0.49 |
| Too fast for conditions | 172 | 1.8 | (2.1) | 78 | 0.92 | 1.72 | 0.52 | 0.39 | 0.68 |
| Too slow for conditions | 107 | 1.0 | (1.8) | 14 | 0.17 | 0.65 | 0.15 | 0.08 | 0.26 |
| Gap acceptance | 31 | 0.3 | (0.6) | 13 | 0.15 | 0.46 | 0.50 | 0.26 | 0.97 |
| Failing to stop/yield | 42 | 0.4 | (0.6) | 19 | 0.21 | 0.65 | 0.52 | 0.30 | 0.90 |
| Recognition Errors | 90 | 0.9 | (1.2) | 34 | 0.4 | (0.9) | 0.43 | 0.29 | 0.65 |
| Hazard Detection | 32 | 0.3 | (0.6) | 9 | 0.1 | (0.3) | 0.32 | 0.15 | 0.69 |
| Inattention/dist raction | 58 | 0.6 | (1.2) | 25 | 0.3 | (0.8) | 0.50 | 0.31 | 0.81 |
| Other | 58 | 0.6 | (1.0) | 23 | 0.2 | (0.8) | 0.44 | 0.27 | 0.73 |
| Driving Errors by Road Type | |||||||||
| Parking Lot | 157 | 14.2 | (21.8) | 57 | 4.7 | (7.8) | 0.39 | 0.28 | 0.55 |
| Residential Rural | 465 | 10.5 | (8.0) | 277 | 6.9 | (10.2) | 0.65 | 0.55 | 0.77 |
| Suburban Commercial | 194 | 10.1 | (9.0) | 85 | 5.2 | (8.6) | 0.50 | 0.38 | 0.66 |
| Urban Commercial | 70 | 9.4 | (16.3) | 58 | 4.4 | (9.4) | 0.55 | 0.37 | 0.83 |
| Highway | 252 | 9.5 | (12.7) | 309 | 9.8 | (16.3) | 1.21 | 0.99 | 1.48 |
| High Risk Secondary Tasks | 554 | 5.8 | (4.6) | 878 | 9.9 | (7.6) | 1.93 | 1.72 | 2.17 |
*
Total number of video segments where each error was observed
^
Estimated using total unique instances where errors were observed. Multiple errors types may occur in each video segment, SD = Standard Deviation
+
Significant values in bold
#
Due to participant withdrawal and limited practice by several teens, data for the final ten hours of practice driving were available for 79 participants