An experimental study to examine whether and how Flemish and Dutch harm prevention messages on gambling advertising affect consumers' gambling-related beliefs and intentions.

Objective: Despite the widespread use of harm prevention messages on gambling advertising, it is unclear whether such messages achieve their goal of encouraging safer gambling behavior and preventing gambling harms. The current research therefore investigates whether and how existing harm prevention messages implemented on gambling advertisements in Belgium and the Netherlands affect consumers' gambling-related beliefs and intentions.

Method: Two experimental studies (N = 169; N = 212) investigate (a) the influence of message prominence and (b) the impact of message framing by comparing the effectiveness of the message "Gamble in moderation" with different types of Flemish and Dutch harm prevention messages (that are currently used in Belgium and the Netherlands) on people's gambling-related beliefs and intentions.

Results: The results of the first experiment show that although the size of a harm prevention message may increase message recognition, it does not affect the message's efficacy. In addition, the second experiment shows that the harm prevention message "Gamble in moderation" increases normative perceptions of gambling (vs. no message), and even enhances gambling intentions among at-risk gamblers compared to no message and other commonly used harm prevention messages. In contrast, exposure to the harm prevention message "What does gambling cost you? Stop in time" makes at-risk gamblers think most about the harms of gambling.

Conclusions: Current harm prevention messages on gambling advertising often promote the concept of responsible gambling, but can have opposite effects than intended, especially among at-risk gamblers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).