Developing a systems thinking-informed questionnaire for understanding decisions to drive tired or sleepy in young adults using Delphi consensus methodology

Sleepiness is implicated in many road safety events for young adults, who are over-represented in road crashes. Yet, system-wide factors that contribute to young adults’ decisions to drive while tired or sleepy are poorly understood. Consequently, the common focus is on individual driver risk factors, rather than a more holistic systems understanding of the contributing influences, meaning we likely overlook key opportunities for intervention and advocacy. This study aimed to develop a novel questionnaire which considers system-wide contributors to decisions to drive tired or sleepy. Drawing on existing literature, a preliminary set of questionnaire items was created and reviewed by twelve Australian experts in sleep science, road safety, and systems thinking. Questions were framed according to Rasmussen's Risk Management Framework to better understand systemic contributors, and we used a modified Delphi methodology with pre-specified targets to achieve consensus. Items were evaluated by all experts for both relevance and clarity using a 7-point Likert scale, with opportunities provided for qualitative feedback and the suggestion of additional items. The result was a 32-item questionnaire after two rounds, with Median scores of 6 and (‘moderately’ and ‘strongly’ agree) for all items in accordance with prespecified criteria. Tools informed by systems thinking are essential for advancing research and policy, and expand our opportunities to collect system-level insights at scale. By moving beyond driver-centric questions, we can identify broader leverage points for intervention, better understand underlying systemic risk factors, and contribute to more effective strategies to reduce road crash risk in young adults. • System-wide factors which affect decisions to drive tired and/or sleepy are poorly understood. • This is particularly the case for young adults. • Using Rasmussen's Risk Management Framework, we consider factors beyond the individual driver. • We provide a consensus-derived questionnaire for use to better understand these factors.