This study assessed US adults’ risk perceptions of tobacco and nicotine products along the FDA-defined risk continuum [4-8], and examined the effect of providing information about reduced exposure to harmful chemicals when using a particular ENDS product – JUUL – compared to smoking. Respondents of various tobacco use status showed a rudimentary understanding of the risk continuum, ordering products in a manner consistent with expert opinion, i.e., Dual Use (that is additive in nature) > Smoking > JUUL > NRT > no use of any tobacco or nicotine product[4-8] . Seeing the message that complete switching to JUUL use results in less exposure to harmful chemicals than does smoking modestly lowered participants’ perceived risk of JUUL, consistent with the previous literature suggesting that accurate information can mitigate risk misperceptions.[33]
Although respondents ordered behaviors appropriately on the risk continuum, their quantified estimates of the relative risks were substantially at variance with the science. For example, respondents assigned NRT medications over 50% the risk they attributed to smoking. This likely reflects the well-documented misperceptions about the risk of NRT [53, 54], which in turn reflects misperceptions about the risks of nicotine and its role in smoking-related harm [55, 56].
Similarly, respondents who did not see the message assigned JUUL use a risk corresponding roughly to 83% the risk of smoking, despite the fact that data has led scientists and medical authorities to conclude that the risk of ENDS use is likely closer to 5% to 15% that of smoking [6, 9, 10, 57]. Seeing the reduced-exposure message lowered respondents’ risk perceptions of JUUL, but even those who saw the message still estimated its risk at 75% that of smoking. Thus, the effect of the message on risk perception of JUUL was modest, well below what scientists regard as likely [58]. Reasons for this may include the fact that some respondents did not believe the message. Also, the message did not specifically claim a reduction in risk, but only reduction in exposure to harmful chemicals, from which many respondents, but likely not all, reasonably inferred reduced risk (referred as “exposure-to-risk halo” by Seidenberg et al.[59]). This inference is recognized in the FDA’s regulation of tobacco products [60], which allows messages of reduced exposure when evidence of reduced risk is not yet available, but where it is “reasonably likely” based on reductions in exposure to toxicants.
The effect of the reduced-exposure message on perceived risk of JUUL was evident in AWS, who are the primary intended audience for this communication. As more favorable relative-risk perceptions are associated with adoption of ENDS [23-26], with switching away from smoking [26-28], and with avoiding resumption of smoking after having switched [26, 29], communicating accurately about reduced exposure to harmful chemicals may help some AWS move towards use of less harmful products to the benefit of public health, consistent with FDA’s strategic plan for reducing the disease burden of smoking [7]. The effect of the message, and of these risk perceptions, on study participants’ intention to use JUUL will be evaluated in a subsequent paper.
The message did not significantly change risk perceptions of JUUL in current dual users. This is likely because dual users already had lower risk perceptions for JUUL, even without being exposed to the message, which may be conveying information they already know and believe. Dual users may have lower perceived risk of JUUL use both because perceiving reduced risk from ENDS may have been what led them to adopt ENDS in the first place [23-26], and because of the tendency for people to see their own behaviors as less risky [61, 62].
Notably, the message increased perceived risks of smoking in AWS and dual users, likely by making salient the crucial role of combustion and smoke inhalation in tobacco-related harm to AWS, as well to others. This may encourage AWS and dual users to stop smoking, which would reduce their risk.
Nonusers of tobacco attributed greater risk to all products and practices than did current users. This may be both a cause and an effect of their non-use status. Nonusers also shifted their risk perceptions of JUUL lower when exposed to the message. It would be unfavorable to public health if this shift in risk perception led nonusers to use ENDS, but this may be unlikely, as even after seeing the message, these groups attributed to JUUL 80% the risk overall of smoking and a 65% risk of developing smoking-related diseases (Figure 2), rating the risk of JUUL use to be about 75 out of 100 (Figure 1).
Consistent with prior research on the effects of message credibility [36, 37], those who doubted or rejected the message assigned higher risk ratings to JUUL. Surprisingly, Message Rejectors reported risk perceptions higher than those of Control respondents who did not see the message at all. Message Rejectors may have been reacting against the message, perhaps because of their perception of the message source (as coming from the company that makes JUUL). It is well established that “source credibility” is low for advertisements [63] and when the source is a tobacco company [36, 64, 65]. JUUL in particular has been highly scrutinized in the media, which may further undermine the message’s credibility.
Message Rejectors may also have come into the study with greater risk misperceptions. This hypothesis is consistent with the finding that Rejectors also assigned higher risk to NRT, whose risk was not addressed by the message. In any case, message acceptance is an important moderator of message effects on risk perceptions, and possibly other outcomes.
Another factor limiting the effect of the message is the single exposure in an artificial study setting. Several studies have suggested that the brief exposure to the message in an experimental setting may have been a limiting factor in the modest effects of a message [66, 67]. Repeat exposure over time in more naturalistic settings, and from more credible sources, may enhance the effect of the message on risk perceptions.
While the Control group was not exposed to the message, they did view an advertisement that explained the concept of ENDS and JUUL; they do not represent the naïve state, but their responses do control for the context in which the message was communicated. The sample was diverse, but it was not fully representative of the US population. Importantly, representativeness is less crucial in a randomized experiment, where the focus is on the effects of the manipulation, rather than on estimating a population parameter [68]. Finally, the study evaluated a particular message expression about a particular product, so some conclusions may not be generalizable to risk messaging or risk perceptions in general, or to other products, even other ENDS.
The study’s strengths include the randomized experimental design, with a large and demographically diverse sample with varied tobacco-use histories. Risk perceptions were evaluated in several ways, and produced convergent results, making the findings robust. The survey items were largely drawn from prior research and were also subject to cognitive testing. Importantly, the message itself is supported by data from multiple studies, is consistent with a message authorized by the FDA under its provisions for reduced-exposure communications, and its wording was pre-tested with the target audience.
In this study, information about reduced toxicant exposure with JUUL, compared to cigarette smoking, shifted risk perceptions of JUUL in a more realistic direction, despite lingering misperceptions. The impact of the message was limited by participants’ skepticism of the information. Conveying accurate information about exposures to harmful chemicals may be one important step towards helping AWS move away from smoking and shift towards less harmful products. This is consistent with FDA’s Center for Tobacco Products’ identification of risk misperceptions as a significant issue that the agency is planning to address through a public education campaign [69].