Testing Mechanisms and Effects of Opposition-Targeted Inoculation and Visual Strategies to Promote Health Policy
Inoculation theory predicts messages forewarning people of opposing arguments can offset the effects of subsequent exposure to oppositional messages. Tests of inoculation rarely explicate the mechanisms of inoculation messages that specify oppositional targets or use visual evidentiary strategies. We test the effects of targeted inoculation and visual imagery on public support for restricting the marketing of sugary drinks to youth. A targeted inoculation message reduced the effects of anti-policy messages on policy support by evoking anger and counterarguing immediately after exposure to the inoculation message, but not after a one-week delay. Adding visual imagery provided no inoculation benefit.