LAUSR

Background Drivers with Attention Deficit Hyperactivity Disorder (ADHD) have been considered to have a 3-4 times higher crash risk than control drivers without ADHD. A core issue which has not been properly dealt with from then on is the role of co-morbid diagnoses which frequently appear together with ADHD, especially Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD), sometimes generically referred to as “conduct problems”. The increased crash risk associated with ADHD diagnosis presented in the literature is often based on studies performed with participants with more than one diagnosis. This means that the co-morbidity may be high and, consequently, the effect of ADHD on traffic safety could be overestimated. This has been shown in a meta-analysis presenting a relative risk of 1.30 instead. The existing research on drivers with ADHD is unsatisfying when it comes to methodology and specifically concerning inclusion and exclusion criteria for participants. This has led to a misunderstanding of the driving ability for people with ADHD, which has been cited and spread in the literature for two decades. People with ADHD diagnosis might suffer from this misinterpretation and the specific effects of ADHD on driving behavior remain unclear. There is a potential for better control for confounding factors, for exposure (mileage) and for co-morbidity, especially CD and ODD. The aim of this project was to examine differences in driving behavior between drivers with ADHD and a control group with drivers without ADHD. Methods In this study conducted in a driving simulator at VTI, 40 drivers diagnosed with ADHD and 20 drivers without ADHD participated, both men and women. The route included urban road, rural road and motorway. No secondary tasks were included and the data collected was driving speed, attention/ reaction time to other road users, and questionnaire. Results Analyses are ongoing and will be presented at the conference. Conclusions Recruiting participants and performing the study was successful. Further conclusions will be presented at the conference.