Comparison of Message and Effects Perceptions for The Real Cost E-Cigarette Prevention Ads.

Perceived message effectiveness (PME) is commonly used in health communication research and practice, yet there has been a dearth of studies comparing different operationalizations of the PME construct. In the present study, we compared the two major types of PME - message perceptions and effects perceptions - among N = 557 young adults. Participants were randomized to one of two conditions: 1) The Real Cost e-cigarette prevention ads developed by the Food and Drug Administration (FDA condition) or 2) information-only e-cigarette control ads developed by the Mayo Clinic (control ad condition). Study predictors were message and effects perceptions measures and actual message effectiveness (AME) outcomes were risk beliefs about vaping and intentions to vape. Results showed that both message perceptions (M = 3.82 vs M = 3.29; p < .001) and effects perceptions (M = 4.13 vs M = 3.82; p < .001) were higher in the FDA ad condition compared to control. Risk beliefs about vaping were also higher in the FDA ad condition than control (M = 3.95 vs M = 3.79; p =.022), but we found no differences in participants' intentions to vape, which were low overall (M = 1.59 in FDA vs M = 1.58 in control). In multivariate analyses adjusting for covariates and including both types of PME, only effects perceptions (not message perceptions) were associated with risk beliefs about vaping (b =.37, p < .001) and intentions to vape (b = -.26, p < .001). Our findings advance PME research by demonstrating the differing nature of message and effects perceptions, and suggest that effects perceptions should be utilized during message pretesting.