Design and procedure
PMT, RECRUITMENT
Study procedures were pre-registered with Clinical Trials and adheres to the requirements of the institutional registry. Data were collected in January 2021. Recruitment began in January 2021 and continued until data collection concluded in April 2021, at which point treatment effects on study outcomes were analyzed. Participants were recruited through digital posters in university student Facebook groups and the Mass Email Recruitment system at the institution. Participants were targeted to participate if they self-identified as a regular vaper (vaping at least 3× in the past 30 days) and were 18 years of age or older while being enrolled within an accredited Canadian university. Participants were allocated a participant ID (XX-YYY) upon enrollment in the study. Questionnaires used to collect data were labeled using participants’ ID and no identifiers were associated with participant ID to protect their anonymity. All communication and procedures (consent forms, distributed incentives, intervention videos, and questionnaire links) were conducted through registered emails of each respective participant. Thus, all participants read the Letter of Information and provided informed written consent prior to participation in the study. Participants were blinded and randomly allocated to one of two treatment groups using block randomization and a random number generator to allocate participants using a 1:1 ratio with block sizes of two. Participants in the PMT present group watched an 8-minute informational video that explained the current research and health risks associated with vaping, within the context of a threat appraisal focus. By design, this video focused on the severity of vaping behaviour on health and the susceptibility of young adult populations to adverse health effects with commentary by healthcare professionals and students who previously identified as regular vapers. Participants in the PMT absent group featured an 8-minute nutritional information video as an attention control (See 