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Master of Arts




Prapavessis, Harry.


A threat appraisal model grounded in Protection Motivation Theory (PMT) determined whether providing health information regarding perceived severity (PS) and perceived vulnerability (PS) of vaping health complications, corroborates with reduced vaping-related intention and habitual behaviour. Seventy-seven regular vapers (22.21 ± 3.47 years) registered within a Canadian university were randomized into one of two groups, wherein the aforementioned threat appraisal information was present. Participants in the experimental group (n = 41) watched an 8-minute information video a week after baseline, following the threat appraisal components of PMT. Those in the attention control group (n = 36) watched an information video on nutrition and healthy lifestyle. Data were collected for PV, PS, vaping intentions, and vaping behaviour at baseline and the following 3 time points after the intervention: Day-7, Day-30, and Day-45. A complete (n = 77) and imputed (n = 416) analysis for missing data revealed a significant treatment group by time interaction effect for PV and PS. Specifically, those in the experimental group reported higher PV and PS scores, compared to their attention control counterparts. For vaping intention, the treatment group by time interaction effect was significant for imputed but not complete data. In both analyses, intentions to vape less, particularly immediately after the intervention was evident in the experimental group but not in the attention control group. For vaping behavior, the treatment group by time interact effect was significant for imputed but not complete data. In both analyses, vaping use after the intervention dropped for both groups, however the drop for those in the experimental group was more pronounced than the drop for those in the attention control group. Both PS and PV were correlated with vaping intention at all assessment time points. Specifically, higher PS and PV scores were associated with intentions to vape less. Weak and inconsistent evidence was provided that intentions to vape less is correlated with actually vaping less. It is suggested through this study that the threat appraisal components of PMT (i.e., PS and PV) can be successfully manipulated among University vapers, which in turn can reduce their intentions to vape and to a lesser extent reduce their actual vaping use. Implications for future vaping intervention research within a public health education framework, are discussed.

Summary for Lay Audience

As a relatively new device in North America, the Lung Association of Canada has been unsuccessful in gaining stricter regulation of vaping products across the country. Since the spike in vaping-related illnesses in 2019, statistics Canada states that young adults were the main users of vaping products, attributed to the mislead understanding that vaping is not harmful to their health. The purpose of this study is to investigate if the use of an 8-minute informational video, following the threat principles of the Protection Motivation Theory (PMT), lowers vaping intention and behaviour in Canadian university students over a 6-week study period. Another goal was to see if the two factors of threat (perceived severity and perceived vulnerability) are individually linked with changes in intention and if that intention can cause actual reductions in vaping use. In this study there were two groups of participants, those who received specific information about the risks of vaping and those who received general facts about nutrition and health. Both groups were asked to complete self-report questionnaires at four separate timepoints within a 6-week study period. From this design it was revealed that PMT health risk information does cause vaping intentions to change and both factors of threat (PS and PV) have a strong effect on intention. However, those intentions do not translate to lowered vaping use. As a result, although using health risk information can cause regular vapers in university to have intentions to vape less, there needs to be more research done on how to convert those intentions into actual behaviour change for vaping.

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