Project Abstract Young people’s use of electronic cigarettes (e-cigarettes) is an emerging public health problem. In 2022, 14.1% of high school students and 3.3% of middle school students in the US reported using e-cigarettes in the previous 30 days, and in 2020, 9.4% of young adult tobacco users were also e-cigarette users. Among youth, 15.9% have used e-cigarette devices for cannabis use in 2021. Further, serious physical and mental health issues, and an increased likelihood of future use of other addictive substances are known to be associated with youth e-cigarette use. Given that nearly 99% of these users begin e-cigarette use before they turn 26, it is vital to gain an accurate understanding of the mechanisms, patterns, associated factors, and long-term consequences of e-cigarette use in this vulnerable population and to develop effective e-cigarette prevention and cessation interventions. However, despite the urgency, only limited measures have yet been developed to assess accurate indicators of youth e-cigarette use behaviors. Accurate measure of frequency and intensity of e- cigarette use presents unique challenges beyond those posed by traditional cigarette use in the general population. Currently, e-cigarette use is assessed based on users’ self-reported surveys, a method that suffers from potential recall bias and inaccurate reports due to social desirability. E-cigarettes include different arrays of products with different characteristics, and some devices last several days before they need to be refilled or discarded, unlike cigarettes, which have a clear beginning and end of use of one unit. It is also difficult to comprehensively assess e-cigarette use, including puff count, duration, and timing for each use, without posing a burden on users. The goal of the current research project is to validate the use of a wrist-worn device (Fitbit) in accurately assessing e-cigarette use in real time. We will use sensors integrated into a wrist-worn device (Fitbit), which is a wearable device that is user friendly for this population. In this way, youth e-cigarette use can be assessed in real time, making it possible to measure e-cigarette use objectively and comprehensively, in participants’ natural environment. We will examine the validity of the e-cigarette use data collected by the wrist-worn device (Fitbit) worn by young adults compared to the video-recorded data in the laboratory setting. Next, we will examine the usability. Additionally, we will examine the validity of the e-cigarette use data collected by the wrist-worn device (Fitbit) compared to the verified data reported daily via their smartphones. Over the long-term, this study will contribute to a comprehensive understanding of patterns and predictors of young people’s e-cigarette use behavior, and to the development of an effective, just-in-time ecological momentary intervention (EMI) for e-cigarette cessation to support efforts to abstain from e-cigarette use based on the feasible and valid data collected via wearable sensor.

Project Narrative Results from this study are expected to have a significant impact because having an accurate assessment of users’ e-cigarette use behaviors will provide a firm foundation for efforts to build the comprehensive understanding of youth e-cigarette use behaviors necessary for developing effective interventions for e- cigarette cessation or abstinence efforts. At the completion of the proposed research, we expect to have demonstrated the feasibility and efficacy of these wearable devices in building and assessing realistic models of real-world e-cigarette use behaviors in this hard-to-reach population. Thus, this study will allow practitioners to develop strong evidence-based strategies for effective interventions, ultimately providing new opportunities for the development of novel approaches to support youth e-cigarette use prevention and cessation programs.