The relations between specific measures of simulated driving ability and functional ability: New insights for assessment and training programs of older drivers

• Relations between older drivers’ driving ability and functional ability are investigated.
• Each specific driving measure is related to a specific set of functional abilities.
• Functional abilities explain a small proportion of the variability in driving ability.
• A driving assessment needs to assess several functional abilities.
• A driving training needs to focus on the right set of functional abilities.

To gain new insights for driving assessment and training, this study had two objectives: (1) to investigate the relations between specific measures of older drivers’ driving ability and demographic/functional ability measures, and (2) to verify the explained variance of these relations to determine the strength of these relations. A sample of 55 older drivers (mean age 76 years) completed a set of functional ability tests as well as a driving simulator test. Results indicate that (1) each specific driving measure is related to a specific set of functional abilities, and (2) only a small proportion of the variability observed in the specific driving measures is explained by demographic variables (3–15%) and by functional abilities (7–36%). For driving assessment programs, it will be necessary to assess several functional abilities to cover the complexity of the driving task. Furthermore, an assessment program focusing solely on demographic and/or functional ability measures, will not be successful in discriminating safe from unsafe older drivers. For driving training programs, it will be necessary to focus on the right set of functional abilities given that specific driving measures are related to different functional abilities. Moreover, a training targeting functional abilities might only have marginal effects on driving ability, given the relatively low amount of driving ability variance that is explained by functional abilities.