Useful Field of View as a Reliable Screening Measure of Driving Performance in People With Parkinson's Disease: Results of a Pilot Study

Abstract

Purpose: To determine the correlations of the Useful Field of View (UFOV), compared to other clinical tests of Parkinson's disease (PD); vision; and cognition with measures of on-road driving assessments and to quantify the UFOV's ability to indicate passing/failing an on-road test in people with PD.

Methods: Nineteen randomly selected people with idiopathic PD, mean age = 74.8 (6.1), 14 (73.7%) men, 18 (94.7%) Caucasians, were age-matched to 104 controls without PD. The controls had a mean age of 75.4 (6.4), 59 (56.7%) men, 96 (92.3%) Caucasians. Both groups were referred for a driving evaluation after institutional review board approval.

Results: Compared to neuropsychological and clinical tests of vision and cognition, the UFOV showed the strongest correlations (r > .75, p < 0.05) with measures of failing a standardized road test and number of driving errors. Among PD patients, the UFOV Risk Index score of 3 (range 1–5) was established as the optimal cutoff value for passing the on-road test, with sensitivity 87 percent and specificity 82 percent, AUC = 92 percent (SE 0.61, p = .002). Similarly, the UFOV 2 (divided attention) optimum cutoff value is 223 ms (range 16–500 ms), sensitivity 87.5 percent, specificity 81.8 percent, AUC = 91 percent (SE 0.73, p = .003). The UFOV 3 (selected attention) optimal cutoff value is 273 ms (range 16–500 ms), sensitivity 75 percent, specificity 72.7 percent, AUC = 87 percent (SE 0.81, p = .007).

Conclusion: In this pilot study among PD patients, the UFOV may be a superior screening measure (compared to other measures of disease, cognition, and vision) for predicting on-road driving performance but its rigor must be verified in a larger sample of people with PD.

Keywords:

• Parkinson's disease
• Useful field of view
• Driving evaluation
• Standardized road course
• Age-matched controls
• Receiver operating characteristics
• Sensitivity and specificity

ACKNOWLEDGMENT

This project was supported by the University of Florida's National Older Driver Research and Training Center. The project was also funded in part by a grant received from the National Parkinson Foundation as a Center of Excellence for Parkinson's Disease and Movement Disorders at the University of Florida.

Notes

¹Visual acuity: Each/both eyes without correction 20/40; if 20/50 or less, applicant is referred to an eye specialist for possible improvement; each/both eyes with correction 20/70; worse eye must be better than 20/200. If one eye blind—other with/without correction 20/40; absolute visual acuity minimum 20/70; bioptic telescopes are not allowed. Visual fields: Minimum field requirement 130 degrees horizontal.

∗ p ≤ .05;

∗∗ p ≤ .01.

∗Correlation is significant at the 0.05 level.

∗∗∗Correlation is significant at the 0.01 level (two-tailed).

∗p ≤ .05;

∗∗ p ≤ .01.