Performance Analysis of Driving Ability (P-Drive): Investigating Construct Validity and Concordance of Australasian Data.

ABSTRACT

On-road assessment is optimal for determining medical fitness-to-drive but unreliable if determined by global pass/fail decisions alone. Occupational therapists need standardized, psychometrically sound on-road scoring procedures. Performance Analysis of Driving Ability (P-Drive) is a promising on-road test developed in Sweden, but it has not been standardized for Australasia. We investigated the psychometric properties and concordance with an on-road decision of data gathered with the Australasian version of P-Drive. P-Drive was administered to older and cognitively impaired drivers (N = 134) aged 18 to 91 years (mean age 68) who were referred to 10 driving clinics in Australia and New Zealand to determine driving performance. Rasch analysis provided evidence for construct validity and concordance of the data gathered. An optimal cut-off score of 85 was set, yielding evidence of good sensitivity at 88% and specificity at 88%. The Australasian version of P-Drive produces valid and reliable data regarding on-road driving performance.

P-Drive A fair and reliable test of fitness-to-drive for medically at-risk drivers in Australasia?In-car driving assessments, conducted by occupational therapists with specialized training, are best for determining if older drivers or drivers with medical conditions are safe to drive because they are conducted in real traffic. However, researchers advise that on-road assessments are unreliable if pass/fail decisions are made without applying consistent and accurate scoring procedures. Drivers undergoing assessments want tests to be fair and equitable, regardless of the tester or location. Performance Analysis of Driving Ability (P-Drive) is a Swedish, gold-standard test of fitness-to-drive. However, P-Drive has not been examined for drivers in Australia and New Zealand. Therefore, we investigated whether P-Drive was a suitable test for drivers in these regions. P-Drive was given to 134 drivers aged 18 to 91 years who were referred to 10 driving clinics in Australia and New Zealand for fitness-to-drive assessments, due to medical conditions or age-related changes that may impact cognitive function. Results indicated that P-Drive was a valid and reliable test of driving ability for medically at-risk drivers in these regions. Evidence indicates the ideal cut-off score for identifying safe drivers, with 88% accuracy, is 85/100.