It is unclear if harm prevention messages used in gambling advertising achieve their purpose. The researchers performed two experimental studies. The first study showed that a larger size version of the harm prevention message, “Gamble in moderation”, increased recognition. But it did not affect what people thought about the risk of gambling and their gambling intention. “Gamble in moderation” is a message commonly shown in gambling advertising in Belgium. The second study compared this message to other harm prevention messages. “Gamble in moderation” increased normative perceptions (e.g., most people gamble) and even gambling intentions among people at-risk of problem gambling. In contrast, people with at-risk gambling thought about the harms of gambling more after they saw the message “What does gambling cost you? Stop in time”.
