DISMANTLING THE ART OF DECEPTION: USING “INOCULATION” TO COMBAT MISINFORMATION FROM MISLEADING CIGARETTE ADVERTISING Stefanie K. Gratale Joseph N. Cappella Misinformation is a growing concern in the public health realm, as it is persistent and difficult to correct. One strategy recently considered to address misinformation is “inoculation”, which leverages forewarning and refutation to defend against a subsequent persuasive message. Here, I aimed to assess whether inoculation can be harnessed to forestall implicitly arising misinformation such as that from misleading natural cigarette ads, which have been shown to prompt widespread misbeliefs. I conducted three randomized online experiments assessing means of inoculating against misinformation. The first tested inoculation tactics to determine whether particular message formats are more effective (i.e., exemplar, narrative, or exposition), and to assess whether inoculations must refute the exact arguments from the misinformation or can more generally match argument themes. The second study tested an attenuated generic versus a specific refutation, and explored results over time. The final study focused on a particular inoculation strategy – highlighting prior deceptive messaging by the persuasive source. Results indicate that inoculations can successfully defend against misinformation from misleading ads; further, they do not need to match exact arguments or even exact themes from the arguments in order to reduce misbeliefs. In fact, high level, generic refutations successfully reduced misbeliefs both immediately and with a time delay, and, crucially, so too did inoculations that included an explicit forewarning but only an implicit refutation. Furthermore, multiple inoculation message formats were successful, and the effectiveness of inoculations was enhanced, to a limited degree, by identifying prior deceptive messaging by the persuasive source. Finally, findings supported counterarguing as a potential mediator of effects of inoculation messages on misbeliefs. The significance of the results here lies in their support for key inoculation components – forewarning and refutation – as well as the much-hypothesized mechanism of counterarguing, when attempting to combat misinformation. The core contribution of these studies is the consistent finding that we can successfully inoculate against implicit misinformation without directly addressing the exact misinformation claims, which is particularly important with implicitly arising, often difficult-to-anticipate misbeliefs from misleading advertising.