Opportunities to maximise the safety benefits of ADAS: A mixed-methods study of self-reported driver understanding, trust and behavioural adaptation

Advanced Driver Assistance Systems (ADAS) have been shown in numerous studies to be effective in reducing road trauma. However, the magnitude of their realised safety benefits depends on how drivers understand, engage with, and respond to these technologies. This study used an exploratory sequential mixed-methods design to examine drivers' engagement with 17 current-generation ADAS functions. Four online focus groups ( N = 33; M age = 43 years, SD = 14; 58% women) explored everyday experiences with ADAS, the insights from which informed an online survey of drivers across Australia ( N = 842; M age = 52 years, SD = 16; 88% men) whose vehicles (model years 2018–2023; average vehicle age = 2.2 years, SD = 1.67) were equipped with at least one of the 17 systems. Topics examined included awareness and self-rated understanding of ADAS, sources of information, trust and acceptability, and self-reported behavioural adaptation (unintended negative consequences of ADAS use) when systems were active. Findings showed that driver understanding of ADAS functionality relied heavily on trial-and-error learning and informal online sources for information. Dealership-provided information was reported infrequently. Awareness and self-rated understanding were highest for established and more salient systems such as blind spot monitoring and lane departure warning, and lowest for newer or less visible systems such as automated emergency steering. Trust and acceptability mirrored these patterns, with lateral automated vehicle control systems attracting lower confidence than longitudinal control systems. Although most drivers denied behavioural change in response to ADAS fitment, some reported reduced situational awareness, fewer blind-spot checks, increased reliance on ADAS, or greater engagement in secondary tasks. Younger drivers reported more behavioural adaptation than older drivers. Overall, the study highlights persistent gaps in drivers' understanding of ADAS. Enhancing the clarity, accessibility, and standardisation of ADAS information may improve trust calibration, support safer engagement, and maximise the safety benefits of ADAS.