Table 4.

Naturalistic driving errors (CDAS) ordered by severity in the overall group.

CDAS items	Mean Rating
	Overall (n=103)	Controls (n=44)	Patients (n=59)
Checks blind spots^a	0.77	0.41	1.03^*
Makes complete stops^a	0.64	0.60	0.67
Pays attention	0.51	0.48	0.54
Awareness of driving on others	0.51	0.32	0.66
Responds to signage	0.48	0.36	0.56
Lane keeping^a	0.42	0.34	0.48
Appropriate response to emergency vehicles	0.38	0.25	0.47
Traffic awareness^a	0.38	0.25	0.47
Right turn	0.37	0.14	0.54^*
Speed control^a	0.36	0.32	0.39

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.

indicates overlap with road test errors.