Warning label messages about the cancer risk associated with alcohol: Effects of causal language

To investigate the effects of causal language in warning messages about alcohol and cancer risk.

In an online factorial experiment conducted in 2023, 799 US adults were randomly assigned to view one of eight messages employing different combinations of causal verbs (e.g., "causes") and modal verbs (e.g., "may") to describe the alcohol-cancer relationship. Analyses compared the effects of causal language on perceptions of causal certainty, alcohol-related cancer risk, message credibility, message reactance, and alcohol consumption intentions.

Causal language did not affect perceived causal certainty, perceived cancer risk, or alcohol consumption intentions, but decreased perceived message credibility and increased reactance. Modal language decreased perceived causal certainty and cancer risk, increased perceived credibility of messages containing "causes," and decreased reactance to all messages.

Causal language in alcohol warning messages has complex, countervailing effects: higher-certainty causal verbs do not increase risk perceptions but increase negative reactance, whereas higher-uncertainty modal verbs decrease risk perceptions but also reactance. These results suggest causal language may pose potential tradeoffs for risk communication efforts, raising the need for caution and more research to understand its effects.