Objective: The purpose of this study was to determine the ability of a visu
al-perception assessment tool, the Motor-Free Visual Perception Test, to pr
edict on-road driving outcome in subjects with stroke.
Design: This was a retrospective study of 269 individuals with stroke who c
ompleted visual-perception testing and an on-road driving evaluation. Drivi
ng evaluators from six evaluation sites in Canada and the United States par
ticipated. Visual-perception was assessed using the Motor-Free Visual Perce
ption Test. Scores range from 0 to 36, with a higher score indicating bette
r visual perception. A structured on-road driving evaluation was performed
to determine fitness to drive. Based on driving behaviors, a pass or fail o
utcome was determined by the examiner.
Results: The results indicated that, using a score on the Motor-Free Visual
Perception Test of less than or equal to 30 to indicate poor visual-percep
tion and >30 to indicate good visual perception, the positive predictive va
lue of the Motor-Free Visual Perception Test in identifying those who would
fail the on-road test was 60.9% (n = 67/110). The corresponding negative p
redictive value was 64.2% (n = 102/159). Univariate logistic regression ana
lyses revealed that older age, low Motor-Free Visual Perception Test scores
and a right hemisphere lesion contributed significantly to identifying tho
se who failed the on-road test.
Conclusions: The predictive validity of the Motor-Free Visual Perception Te
st is not sufficiently high to warrant its use as the sole screening tool i
n identifying those who are unfit to undergo an on-road evaluation.