Table 2 Adjusted relative risks and ratios of relative risks, population-based fatal crash involvement rates of older drivers associated with changes in driver license renewal policies, United States, 1986–2011

Ratio of relative risks (95% confidence interval)

Renewal period (1 year reduction)

Reference

0.99 (0.92–1.08)

1.03 (0.97–1.10)

1.00 (0.93–1.08)

1.05 (0.95–1.17)

0.96 (0.88–1.06)

0.94 (0.88–1.00)

0.95 (0.89–1.02)

In-person renewal

-

1.01 (0.77–1.33)

0.86 (0.66–1.11)

0.85 (0.65–1.10)

0.92 (0.69–1.23)

0.74 (0.48–1.15)

0.91 (0.67–1.24)

0.69 (0.48–0.97)

Vision testing (overall)

-

1.01 (0.86–1.20)

1.08 (0.89–1.29)

1.06 (0.92–1.23)

1.00 (0.84–1.19)

1.05 (0.79–1.40)

0.93 (0.80–1.07)

0.93 (0.78–1.10)

Vision testing (at in-person renewal)

-

1.01 (0.83–1.23)

1.13 (0.93–1.38)

1.16 (0.96–1.39)

0.98 (0.81–1.18)

1.15 (0.85–1.56)

0.98 (0.80–1.19)

1.06 (0.84–1.32)

Vision testing (without in-person renewal)

-

1.03 (0.76–1.39)

0.98 (0.67–1.44)

0.91 (0.70–1.19)

1.06 (0.70–1.61)

0.85 (0.41–1.76)

0.81 (0.63–1.03)

0.64 (0.49–0.85)

Knowledge test (at in-person renewal)

-

0.83 (0.55–1.26)

0.98 (0.74–1.28)

0.98 (0.64–1.51)

0.95 (0.76–1.19)

0.89 (0.70–1.13)

0.93 (0.74–1.17)

0.97 (0.76–1.24)

On-road driving test (at in-person renewal) ^a

-

-

-

-

-

-

-

-

Mandatory reporting law for physicians ^b

-

1.03 (0.87–1.23)

1.01 (0.86–1.19)

0.98 (0.83–1.16)

1.03 (0.88–1.21)

1.00 (0.86–1.16)

0.98 (0.84–1.15)

0.96 (0.82–1.14)

Adjusted relative risk (95% confidence interval)

Renewal period (1 year reduction)

1.03 (0.98–1.09)

1.03 (0.97–1.09)

1.07 (1.02–1.11)

1.03 (0.98–1.09)

1.09 (1.00–1.19)

1.00 (0.92–1.08)

0.97 (0.93–1.01)

0.99 (0.95–1.03)

In-person renewal

1.05 (0.84–1.31)

1.06 (0.91–1.25)

0.90 (0.79–1.03)

0.89 (0.78–1.02)

0.97 (0.80–1.16)

0.78 (0.54–1.14)

0.96 (0.77–1.19)

0.72 (0.55–0.94)

Vision testing (overall)

0.96 (0.86–1.07)

0.97 (0.85–1.10)

1.03 (0.89–1.20)

1.02 (0.93–1.12)

0.96 (0.83–1.10)

1.01 (0.78–1.31)

0.89 (0.80–0.98)

0.89 (0.77–1.02)

Vision testing (at in-person renewal)

0.94 (0.80–1.11)

0.95 (0.85–1.06)

1.06 (0.95–1.19)

1.09 (1.00–1.18)

0.92 (0.84–1.01)

1.08 (0.83–1.40)

0.92 (0.82–1.03)

0.99 (0.85–1.16)

Vision testing (without in-person renewal)

0.99 (0.87–1.12)

1.01 (0.77–1.34)

0.97 (0.68–1.39)

0.90 (0.71–1.14)

1.05 (0.70–1.56)

0.84 (0.41–1.72)

0.80 (0.65–0.98)

0.64 (0.50–0.81)

Knowledge test (at in-person renewal)

1.13 (0.93–1.38)

0.94 (0.65–1.36)

1.11 (0.92–1.33)

1.11 (0.76–1.62)

1.07 (0.97–1.18)

1.01 (0.89–1.15)

1.05 (0.94–1.18)

1.10 (0.94–1.27)

On-road driving test (at in-person renewal)

-

-

-

-

1.00 (0.93–1.08)

0.96 (0.85–1.07)

1.09 (0.97–1.23)

1.02 (0.92–1.14)

Mandatory reporting law for physicians ^b

1.07 (0.94–1.21)

1.10 (0.99–1.24)

1.08 (0.98–1.20)

1.05 (0.94–1.17)

1.11 (1.01–1.21)

1.07 (0.98–1.16)

1.05 (0.96–1.16)

1.03 (0.93–1.14)