Carbohydrate deficient transferrin in a driver's license regranting program.

AIMS: Carbohydrate deficient transferrin (CDT) is a common diagnostic marker for detecting chronic alcohol abuse. For over 2.5 years, it has been used in traffic medicine among subjects applying for driver's license renewal or regranting in Belgium. We report on data collected during the program and provide an estimation of an applicable cut-off point in forensic situations. Using this cut-off, the success of the driver's license regranting program is evaluated. METHODS: CDT was assayed at Ghent University Hospital by capillary zone electrophoresis, measured on the Capillarys 2™ system, in 3977 subjects applying for driver's license regranting. Determination of a cut-off was done by using Bhattacharya statistics and by adding a measurement uncertainty interval. The outcome of the program was evaluated by monitoring CDT values for 163 subjects during one entire year. RESULTS: In 3977 subjects (3481 males and 496 females), CDT values were significantly higher in men compared with women, but there is no need for a gender-specific cut-off value. Drunk drivers under the age of 30 have significantly lower CDT values than older subjects, and a separate cut-off could be calculated. A general cut-off of 2.3% CDT was calculated for the entire study population. Using this cut-off value for evaluating the outcome of the program for 163 subjects, the percentage offenders at the beginning (29%) decreased to 8% after 1 year. CONCLUSION: Applying a marker for chronic alcohol abuse such as CDT for driver's license renewal or regranting is a powerful tool. Analysis of data collected over 2.5 years reveals a favorable outcome of the program and a useful cut-off point could be determined.

Retraining moderately impaired stroke survivors in driving-related visual attention skills.

BACKGROUND: Visual inattention is a major cause of road accidents and is a problem commonly experienced after stroke. PURPOSE: This study investigated the effects of 2 training programs on performance in the Useful Field of View (UFOV), a validated test of driving-related visual attention skills. METHOD: Data from 69 first-ever, moderately impaired stroke survivors who participated in a randomized controlled trial (RCT) to determine the effects of simulator training on driving after stroke were analyzed. In addition to regular interventions at a rehabilitation center, participants received 15 hours of either simulator-based driving-related training or non-computer-based cognitive training over 5 weeks. RESULTS: Total percentage reduction in UFOV and performance in divided and selective attention and speed of processing subtests were documented at 6 to 9 weeks (pretraining), 11 to 15 weeks (posttraining), and 6 months post stroke (follow-up). Generalized estimating equation (GEE) model revealed neither group effects nor significant interaction effects of group with time in the UFOV total score and the 3 subtests. However, there were significant within-group improvements from pre- through posttraining to follow-up for all the UFOV parameters. Post-hoc GEE analysis revealed that most improvement in both groups occurred from pre- to posttraining. CONCLUSION: Both training programs significantly improved visual attention skills of moderately impaired stroke survivors after 15 hours of training and retention of benefit lasted up to 6 months after stroke. Neither of the training programs was better than the other.

Confirmation of the accuracy of a short battery to predict fitness-to-drive of stroke survivors without severe deficits.

OBJECTIVE: The aim of this prospective study was to confirm the accuracy of a short assessment battery, used previously in a study to predict fitness-to-drive after stroke, in a new cohort of stroke survivors without severe deficits. DESIGN: A prospective study. SUBJECTS: A total of 43 (39 men and 4 women) consecutive survivors after stroke who were not severely impaired and who performed the pre-driving assessment, which included a standardized on-road test at the Belgian Road Safety Institute in Brussels, Belgium. On average, participants were 6 months post-stroke, independently ambulant with or without assistive devices, possessed valid drivers' licenses and actively drove prior to stroke onset. METHODS: Fitness-to-drive decisions based on performance in 15 tests of a full-scale assessment battery were predicted using only the scores from the 3 predictive tests previously identified. RESULTS: When the discriminant equation from the previous study including performance in the 3 tests (figure of Rey, visual neglect (lateralized mean reaction time) and on-road test) was applied, 37 (86%) of the 43 participants were correctly predicted to pass or fail the pre-driving assessment. The sensitivity and specificity of the predictions were 77% and 92%, respectively. CONCLUSION: This study shows that the short assessment battery is a good predictor of fitness-to-drive in stroke survivors with moderate physical and cognitive impairments.

The validity of a road test after stroke.

OBJECTIVES: To determine the validity of a road test performed by stroke patients in Belgium and to reestablish its reliability. DESIGN: Prospective study of a predriving evaluation. SETTING: University hospital in Belgium. PARTICIPANTS: Thirty-eight patients with sequelae of first-ever stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Performance in the Stroke Driver Screening Assessment (SDSA) and on a road test. RESULTS: Interrater reliability of the road test subitems was moderate to substantial (weighted kappa range, .44-.78). Item-per-item reliability varied from moderately high (intraclass correlation coefficient [ICC]=.63) to very high (ICC=.87). The reliability of the overall performance in the road test was very high (ICC=.83). For the criterion validity of the road test, 78.9% of the subjects were correctly classified when the judgments of the principal evaluator were compared with outcomes of the SDSA. Agreement in classification between the principal evaluator and a state-registered evaluator's judgments was 81.6%. The sensitivity and specificity of the agreement were very high (80.6%) and perfect (100%), respectively. CONCLUSIONS: The road test is a reliable and valid test of driving ability after stroke.

Reliability of a road test after stroke.

OBJECTIVE: To determine the reliability of the road test performed by stroke patients. DESIGN: Prospective study of a 6-month predriving evaluation. SETTING: Driving safety center in Belgium. PARTICIPANTS: Thirty patients with sequelae of stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Results of driving performance as judged by 2 assessors from the Center for Determination of Fitness to Drive and Car Adaptations (CARA), in a car fitted with a video camera. A third assessor also evaluated all the video recordings. Interrater reliability was evaluated by comparing results from real-life performance and video recording, as judged by the CARA assessors and video judgments between CARA assessors and the third assessor. RESULTS: Most subitems of the road test showed more than 80% scoring agreement between the various evaluations. Intraclass correlation coefficients (ICCs) of the items varied from -.08 to 1.0. The ICC of the overall performance was.62 when real-life scores were compared with video evaluations and.80 in video versus video comparison. CONCLUSION: The reliability of assessing overall performance of stroke patients in the road test is moderately high and better when assessed using the same evidence. Yet, the reliability of some items needs further attention.

Determinants of driving after stroke.

OBJECTIVE: To identify variables that best predict a team's decision of driving ability in stroke patients from a predriving assessment. DESIGN: Retrospective study of a 2-year predriving evaluation. SETTING: Belgian Institute for Road Safety. PARTICIPANTS: One hundred four patients with sequelae of first stroke. INTERVENTIONS: Predriving assessments and road test. MAIN OUTCOME MEASURES: The suitability to resume driving based on a team decision and performance in the road test. RESULTS: Forty-one patients (39.4%) were judged suitable, 45 (43.3%) not immediately suitable, and 18 (17.3%) not suitable to drive. Correlation coefficients and comparisons between groups revealed that most variables had significant individual relationships with the team decision and performance on the road test. After logistic regression analysis, side of lesion, kinetic vision, visual scanning, and a road test led to the best model in predicting the team decision (R(2) =.53). The road test was the most important determinant (R(2) =.42). Multiple regression analysis showed that the combination of acuity of left and right eyes and the figure of Rey was the best subset to predict the road test (R(2) =.28). CONCLUSION: The predictive accuracy of the team's decision is limited, and the road test is even lower. Inclusion of more real-road-related tests in the predriving assessment is necessary.