The effectiveness of an advisory intelligent speed adaptation (ISA) system for Victorian repeat speeders
The Repeat Speeders Trial (RST) aimed to evaluate two interventions to assist Victorian recidivist speeders to reduce speeding: a speed behaviour program and advisory ISA. This paper presents the findings from the on-road trial of ISA. The trial aimed to evaluate the effectiveness of an advisory ISA system, either coupled with demerit point removal or not, in reducing recidivist speeders’ speeding behaviour. A total of 86 repeat speeders from Victoria participated in the ISA trial. Forty of the drivers were exposed to advisory ISA as part of their everyday driving for a period of 12 weeks and then monitored via a data logger for a further eight weeks (Speed Alert group). Another group of 46 drivers, who were not exposed to ISA but monitored for 20 weeks, acted as a control group (Speed Data group). Approximately half of the participants in each group, who were selected at random, had three demerits points from their last speeding offence removed from their driving record. When ISA was active, the Speed Alert group had a statistically significant reduction in mean speed, time spent exceeding the speed limit, and the time taken to return to the speed limit when it was exceeded compared to the Speed Data group. When ISA was not active, there was no difference in speeding behaviour between groups. Demerit point removal did not influence the effectiveness of ISA. These results are promising given that this is one of only two studies published worldwide to demonstrate the effectiveness of ISA in a sample of recidivist speeders.