Table 3.

Road test (RIRT) errors ordered by severity in the overall group.

RIRT	Mean Rating
	Overall (N=103)	Controls (n=44)	Patients (n=59)
Checks blind spotsa	0.87	0.62	1.06*
Uses mirrors for lane change	0.25	0.13	0.34*
Uses mirrors	0.19	0.08	0.27*
Traffic awarenessa	0.19	0.10	0.26*
Speed controla	0.18	0.14	0.21
Approaches intersection at appropriate speed	0.17	0.19	0.16
Makes complete stopsa	0.17	0.12	0.21
Proceeds timely	0.17	0.09	0.23*
Brakes smoothly and accurately	0.14	0.13	0.15
Lane keepinga	0.14	0.07	0.20*

^*Note. denotes significantly poorer performance in the cognitively impaired group compared to the healthy participants; ratings were made on Likert scale ranging from 0-2 (0=intact; 1=mildly impaired; 2=moderately-severely impaired);

^aindicates overlap with naturalistic errors.