The SFST includes the Horizontal Gaze Nystagmus test, the Walk and Turn test and the One Leg Stand test. Several studies report the reliability and validity of the SFST to detect alcohol intoxication as low as 0.08% BAC. Victoria Police, Australia, have recently included the SFST in law enforcement, not to test for alcohol intoxication, but to test for drug impairment. Victoria Police, by law, must establish that the driver being prosecuted was impaired to a degree equivalent to a BAC above 0.10%, irrespective of the level and class of drug found in the drivers specimen. Since no studies have clearly established the relationship between SFST performance and driving impairment this study examined the relationship between performance on the SFST and performance on a driving task. The aim of this study was to establish the accuracy of the SFST in detecting driving impairment after the administration of cannabis. Forty participants were administered the SFST and a driving task in placebo, 1.74% THC and 2.93% THC conditions. The administration of the SFST resulted in 73% correct classification of the sample as either impaired or not impaired on the driving task after the administration of cannabis. The results indicated that the OLS test was the best predictor of driving ability and the inclusion of a 'new' sign HMJ (head movements/jerks) scored in the HGN test, improved the accuracy in detecting impairment. (Author/publisher) For the covering abstract of the conference see ITRD Abstract No. E201067.
Samenvatting