Nonsmokers' Responses to Online E-Cigarette Commercials: Effects of Argument Quantity and Celebrity Endorsement Paper Resubmitted to Substance Use and Misuse.

: With mounting evidence on health risks caused by e-cigarette consumption, it is of great necessity to explore not only smokers' but also nonsmokers' responses to e-cigarette marketing messages, such as online commercials. Employing both psychophysiological and self-report measures, this study examined nonsmoking young adults' cognitive, emotional, and attitudinal reactions to two major message features used in e-cigarette commercials: argument quantity and endorsement type. : The experiment used a 2 (endorsement type: celebrity and average citizen) × 2 (argument quantity: low and high) × 2 (message repetition) within-subjects design. Continuous heart rate (indicative of attention) and skin conductance activity (indicative of emotional arousal) were measured during ads viewing. Self-reported ad liking and vaping urge were assessed immediately after participants finished watching each commercial. : Results showed that compared to high argument quantity, low argument quantity elicited more attention, evoked higher emotional arousal, and generated stronger ad liking and vaping urge. Additionally, compared to average-citizen endorsement, the presence of celebrity endorsement elicited higher attention and lower emotional arousal in nonsmoking young adults. There was a significant interaction effect of endorsement type and argument quantity on ad liking. : For nonsmoking young adults, low argument quantity commercials might have the greatest impact in initiating vaping behavior, which has implications for regulatory policies regarding e-cigarette. Celebrity endorsement was effective in catching nonsmokers' attention but had limited effects on emotional involvement and product adoption. The implications of the findings were finally discussed in more details in the manuscript.