Predicting fitness to drive using the visual recognition slide test (USyd).

Objective: The authors examined the construct and predictive validity and internal reliability of the Visual Recognition Slide Test developed at the University of Sydney (VRST-USyd).

Method: A historical cohort study using retrospective descriptive analysis of VRST-USyd scores and on-road driving performance for 838 drivers with impairments was conducted.

Results: Rasch analysis provided evidence for the construct validity and internal reliability of the VRST-USyd. Goodness-of-fit statistics for all items were acceptable. The test had high participant and item reliability indexes and separated the participants into four groups with varying levels of skill. Using a cutoff score of 95/164, the sensitivity of the test was 81%, and the specificity was 90%. However, when coupled with clinicians' judgment of participants' awareness of their driving performance during the on-road assessment, this score improved.

Conclusion: There is evidence for reliability and construct and predictive validity of the VRST-USyd. The measurement of awareness requires further research.