The effect of bioterrorism messages on anxiety levels.

Public health messages sometimes use graphic language to discourage health-adverse behaviors. However, such messages could provoke adverse stress and anxiety reactions. To assess whether public health messages on bioterrorism might measurably increase stress and anxiety, we conducted a randomized controlled trial in which potent and neutral messages were randomly allocated to 116 graduate students. Pre- and post-message anxiety scores of the State-Trait Anxiety Inventory (STAI), a validated instrument, were recorded, and within- and between-group score changes compared. Reading the potent message significantly (p=.003) elevated STAI anxiety scores, while reading the neutral messages decreased scores (p<.001). The between-group difference was also statistically significant (p=.001). Potent smoking and drunk-driving cessation messages have clear benefits, but messages about bioterrorism do not. Our findings provide evidence that such messages have at least the potential of harm, so that weighing benefits and risks of such messages is warranted.