Table 2.
Incidence rates per mile of driving for being a driver in a fatal crash by age, year, and graduated driver licensing exposurea
| Age (yr) | Year | Graduated driver licensing exposureb | No. of drivers in fatal crashes | Rate per 100 million miles driven | Adjusted incidence rate ratio per miles (aIRRm) (95% CI)c |
|---|---|---|---|---|---|
| 16 | 1995–1996 | Absent | 1,310 | 12.5 | |
| 2001–2002 | Absent | 319 | 7.8 | ||
| Present | 707 | 8.5 | |||
| 2008–2009 | Absent | 41 | 9.8 | ||
| Present | 486 | 8.1 | |||
| 0.83 (0.65, 1.06) | |||||
| 17 | 1995–1996 | Absent | 1,431 | 6.7 | |
| 2001–2002 | Absent | 453 | 8.6 | ||
| Present | 956 | 7.2 | |||
| 2008–2009 | Absent | 59 | 5.7 | ||
| Present | 791 | 5.5 | |||
| 1.03 (0.80, 1.35) | |||||
| 18 | 1995–1996 | Absent | 1,703 | 6.4 | |
| 2001–2002 | Absent | 523 | 6.3 | ||
| Present | 1,279 | 6.2 | |||
| 2008–2009 | Absent | 84 | 5.6 | ||
| Present | 1,170 | 4.8 | |||
| 1.01 (0.84, 1.23) | |||||
| 20–24 | 1995–1996 | Not applicable | 7,004 | 3.7 | |
| 2001–2002 | Not applicable | 7,237 | 3.3 | ||
| 2008–2009 | Not applicable | 5,587 | 2.8 |
Abbreviation: aIRRm: adjusted incidence rate ratio per miles driven; CI: confidence interval; GDL: graduated driver licensing.
a
Data from the National Household Travel Survey and Fatality Analysis Reporting System.
b
Exposure to GDL means living in a state that has graduated driver licensing laws to restrict adolescent driving.
c
Adjusted incidence rate ratios (aIRRm) compare the rates per miles driven for drivers exposed to GDL with those not exposed, adjusted for changes in rates over time as well as changes among drivers 20–24 years.