The Advancing Understanding of Transportation Options (AUTO) study: design and methods of a multi-center study of decision aid for older drivers.

Background: Decision-making about when to stop driving for older adults involves assessment of driving risk, availability of support or resources, and strong emotions about loss of independence. Although the risk of being involved in a fatal crash increases with age, driving cessation can negatively impact an older adult's health and well-being. Decision aids can enhance the decision-making process by increasing knowledge of the risks and benefits of driving cessation and improve decision quality. The impact of decision aids regarding driving cessation for older adults is unknown.

Methods: The Advancing Understanding of Transportation Options (AUTO) study is a multi-site, two-armed randomized controlled trial that will test the impact of a decision aid on older adults' decisions about changes in driving behaviors and cessation. AUTO will enroll 300 drivers age ≥ 70 years with a study partner (identified by each driver); the dyads will be randomized into two groups (n = 150/group). The decision aid group will view the web-based decision aid created by Healthwise at baseline and the control group will review information about driving that does not include evidence-based elements on risks and benefits and values clarification about driving decisions. The AUTO trial will compare the effect of the decision aid, versus control, on a) immediate decision quality (measured by the Decisional Conflict Scale; primary outcome); b) longitudinal psychosocial outcomes at 12 and 24 months (secondary outcomes); and c) longitudinal driving behaviors (including reduction or cessation) at 12 and 24 months (secondary outcomes). Planned stratified analyses will examine the effects in subgroups defined by cognitive function, decisional capacity, and readiness to stop driving.

Discussion: The AUTO study is the first large-scale randomized trial of a driving decision aid for older adults. Results from this study will directly inform clinical practice about how best to support older adults in decision-making about driving.

Trial Registration: ClinicalTrials.gov : NCT04141891 . Registered on October 28, 2019. Located at https://clinicaltrials.gov/ct2/show/NCT04141891.