Changing driver behaviour during floods using an e-health imagery intervention

The intervention is an online tool that uses a series of infographic videos in which participants are prompted to engage in exercises using imagery and planning to change behaviour their beliefs and intentions toward driving into floodwater. The intervention integrates implementation intentions and mental imagery behaviour change techniques to form a novel implementation imagery intervention. The study will be administered online using the Qualtrics online survey tool. All participants will complete a baseline survey, an activity (different for intervention and control groups), and a survey immediately post-intervention at the first time point. Four weeks later, all participants will complete a follow-up survey. Between the baseline and post-intervention surveys, participants randomly assigned to the intervention group will complete a series of activities constituting the implementation imagery intervention. The activities will run for 10 to 15 minutes and will be delivered in the form of videos embedded within the online survey tool. Video 1 will include factual information to educate participants about the risks of driving into floodwater and will then provide information to encourage participants to form a goal of avoiding driving into floodwater if they encounter it on their route. Video 2 will guide participants through a process mental simulation followed by a short writing task where participants will be asked to record the things they imagined. Video 3 will guide participants through an outcome mental simulation followed by a short writing task where participants will be asked to record the things they imagined. Two questions will be embedded within the baseline (T1) survey to assess whether participants are reading instructions properly or carelessly responding (Maniaci & Rogge, 2014; Schroder, Dawood, Yalch, Donnellan, & Moser, 2016). The questions instruct the choice of a particular answer so that it is not possible to answer the question incorrectly if the item is read carefully (e.g., “please choose option two to ensure you are paying attention”). Participants who do not answer both of the items correctly will be excluded prior to randomisation. Fidelity of the intervention will also be assessed using a modified version of a four-item scale developed by Knäuper et al. (2011). The items assess vividness, clarity, detail, and ease of imagery on 7-point scales (e.g., “How CLEAR was the mental image that you had of yourself avoiding driving through the floodwater?”).