PROJECT SUMMARY E-cigarette use (vaping) in 18-24-year-olds is a public health crisis. It is an urgent public health priority to communicate to young adults about the health harm of vaping to stop and prevent them from vaping. However, effective communication has become challenging in the new age of health misinformation and low trust in health experts. My goal is to investigate the role of a trusted source and strategic message presentation to increase young adults’ acceptance of e- cigarette education messages to impact their behavior. In this two-phased study, I will determine an optimal source and message presentation type for young adult vapers and non-vapers, respectively (K99) and examine the effects of messages optimized for source and presentation on young adults’ vaping cessation and vaping prevention (R00). In phase 1 (K99), I will use a multi-method approach to examine two source (expert and peer) and two message presentation types (one-sided and two-sided) to identify the optimal message type for each vaping status population. First, I will use crowdsourcing testing to collect self-report measures on message acceptance, source trust, message reactance, and harm perceptions. Second, I will use psychophysiological testing to measure participants’ eye-tracking, heart rate, and skin conductance to assess their visual attention, orienting responses, and arousal during message exposure. I will produce a single dataset integrating the crowdsourced and psychophysiological data to determine the optimal source and presentation type for vapers and non-vapers. In phase 2 (R00), I will use a text messaging intervention in a randomized trial to examine the behavioral effects of messages optimized for source and presentation to one’s vaping status (vapers and non-vapers). Participants in each vaping status will be randomized to either the treatment (receiving e-cigarette education messages with a source and presentation type optimized to one’s vaping status) or control arm (receiving non-tobacco health messages) via text messaging over the course of 6 months. I will examine vaping cessation rates among vapers and vaping initiation rates among non-vapers. Results will inform the public health communication campaign development and may apply to other public education campaigns to reduce tobacco use in young people.

PROJECT NARRATIVE Despite the increased effort to curtail e-cigarette use in young adults, the current public health communication campaign messages may fail to influence young adults’ e-cigarette harm perceptions and behavior. Vapers and non-vapers may trust different health information sources and respond differently to messages based on how they are presented, but little research has examined the effects of these communication principles. The proposed study uses online and in-lab studies (Phase 1) and a randomized trial (Phase 2) to understand the role of using an optimal source (expert and peer) and message presentation type (one sided and two sided) in e-cigarette education messages to increase young adult vapers and non-vapers’ message acceptance and change their vaping behavior.