Table 2. Rate of at-fault motor vehicle collisions (MVC) per person-miles driven by visual field impairment.

	At- Fault MVCs	Person-Miles	At-Fault MVC Rate (per million miles)	RR (95% CI)	RR (95% CI)*
Overall	57	25,555,560	2.23	---	---
Threshold
Not severely   impaired	39	19,543,112	2.00	1.00	1.00
Severely impaired	18	5,945,927	3.03	1.52 (0.87-2.65)	1.49 (0.81-2.74)
Total Deviation
Not severely   impaired	39	19,670,715	1.98	1.00	1.00
Severely impaired	18	5,818,324	3.09	1.56 (0.89-2.73)	1.50 (0.82-2.74)
Pattern Deviation
Not severely   impaired	35	19,818,635	1.77	1.00	1.00
Severely impaired	22	5,670,404	3.88	2.20 (1.29-3.75)	2.13 (1.21-3.75)

^*Adjusted for age, gender, race and visual acuity.