Table 3.

Negative Binomial Regression Models—Hospitalized Drivers According to State Laws

Age group (years)		Mandatory physician reporting	Physician reporting (Protected)	In-person renewal	Vision testing when in-person	Road test
60–64	States without law	25,757	10,448	3,816	6,875	Not applicable to age group
	States with law	4,258	19,567	26,199	23,140
	Adjusted incident RR (95% CI) M1	0.96 (0.79–1.17)	1.02 (0.84–1.25)	0.87 (0.67–1.13)	0.77 (0.62–0.94)*
	Adjusted incident RR (95% CI) M2	0.96 (0.74–1.23)	1.01 (0.84–1.21)	0.87 (0.67–1.14)	0.77 (0.61–0.98)*
	Adjusted incident RR (95% CI) M3	0.88 (0.71–1.10)	0.99 (0.87–1.12)	0.92 (0.77–1.11)	0.88 (0.78–0.98)*
65–69	States without law	20,710	8,443	3,122	5,611	Not applicable to age group
	States with law	3,348	15,615	20,936	18,447
	Adjusted incident RR (95% CI) M1	1.03 (0.83–1.29)	0.98 (0.81–1.20)	0.88 (0.66–1.16)	0.78 (0.62–0.98)*
	Adjusted incident RR (95% CI) M2	1.03 (0.79–1.35)	0.98 (0.82–1.17)	0.90 (0.68–1.19)	0.80 (0.61–1.03)**
	Adjusted incident RR (95% CI) M3	0.95 (0.75–1.20)	0.95 (0.84–1.07)	0.97 (0.82–1.14)	0.92 (0.78–1.08)
70–74	States without law	19,153	7,672	2,946	5,351	Not applicable to age group
	States with law	2,946	14,427	19,153	16,748
	Adjusted incident RR (95% CI) M1	1.00 (0.82–1.23)	1.05 (0.86–1.27)	0.82 (0.65–1.05)	0.76 (0.62–0.93)*
	Adjusted incident RR (95% CI) M2	1.00 (0.78–1.27)	1.06 (0.88–1.27)	0.86 (0.67–1.09)	0.81 (0.63–1.03)**
	Adjusted incident RR (95% CI) M3	0.90 (0.73–1.12)	1.03 (0.91–1.15)	0.92 (0.81–1.06)	0.90 (0.79–1.03)
75–79	States without law	19,061	7,728	2,980	5,336	21,260
	States with law	2,987	14,320	19,068	16,712	788
	Adjusted incident RR (95% CI) M1	1.02 (0.81–1.28)	1.03 (0.85–1.26)	0.86 (0.69–1.08)	0.81 (0.65–0.99)*	0.87 (0.75–1.01)
	Adjusted incident RR (95% CI) M2	1.03 (0.77–1.38)	1.04 (0.86–1.26)	0.90 (0.72–1.12)	0.85 (0.66–1.08)	0.88 (0.77–1.01)**
	Adjusted incident RR (95% CI) M3	0.95 (0.72–1.25)	1.00 (0.87–1.16)	0.95 (0.82–1.1)	0.93 (0.79–1.09)	1.01 (0.9–1.13)
80–84	States without law	16,917	6,828	2,638	4,859	18,947
	States with law	2,725	12,814	17,004	14,783	695
	Adjusted incident RR (95% CI) M1	0.97 (0.77–1.21)	1.03 (0.85–1.24)	0.93 (0.72–1.20)	0.83 (0.67–0.97)*	0.94 (0.79–1.12)
	Adjusted incident RR (95% CI) M2	0.99 (0.74–1.31)	1.03 (0.86–1.24)	0.94 (0.72–1.23)	0.84 (0.66–1.06)	0.93 (0.78–1.11)
	Adjusted incident RR (95% CI) M3	0.90 (0.70–1.15)	0.99 (0.87–1.13)	1.02 (0.86–1.20)	0.92 (0.80–1.06)	1.12 (0.97–1.28)
85 +	States without law	12,136	4,750	1,979	3,483	13,729
	States with law	2,104	9,490	12,261	10,757	511
	Adjusted incident RR (95% CI) M1	1.00 (0.84–1.20)	1.07 (0.9–1.27)	0.86 (0.67–1.09)	0.87 (0.72–1.04)	1.00 (0.81–1.24)
	Adjusted incident RR (95% CI) M2	0.99 (0.79–1.23)	1.10 (0.93–1.29)	0.86 (0.66–1.14)	0.90 (0.72–1.12)	1.02 (0.84–1.25)
	Adjusted incident RR (95% CI) M3	0.92 (0.76–1.11)	1.07 (0.96–1.19)	0.97 (0.82–1.15)	1.01 (0.91–1.11)	1.19 (1.05–1.35)*

Notes: M1–Adjusted for the natural log of licensed drivers in each specified age cohort, and patient’s sex and urban or rural location. Also adjusted for state’s primary seatbelt enforcement law, state unemployment rate, annual state total precipitation, state per capita fuel consumption, access to trauma centers, urban speed limits, and license renewal length. The dependent variable is the count of MV-crash hospitalizations of drivers per specified age cohort. CIs were estimated based on a GEE autoregressive first-order correlation structure at the state level and results reported are based on empirical standard error estimates.

M2–Also adjusted for regional similarities.

M3–Also adjusted for the State’s number of hospitalized drivers aged 55–59 years.

CI = confidence interval; GEE = generalized estimating equation.

*p < .05. **p < .10.