There, But Invisible: Warning Messages in Czech Gambling Advertising During Football Broadcasts

Introduction: Gambling advertising during live sports broadcasts raises significant public health concerns, yet regulatory compliance (particularly regarding warning messages) remains underexplored. This study aims to evaluate how common warning messages are and how much screen space they occupy in gambling adverts during live top-tier Czech football broadcasts. Methods: A total of 1,824 gambling adverts were systematically analysed across 32 top-tier Czech football matches. Variables included the presence of mandatory warnings (about age restrictions and potential addiction) and safe gambling messages (SGM), along with their delivery methods, gambling types, match segments, and screen coverage. Warning message sizes were measured using pixel-by-pixel calculations. Nonparametric tests (Mann-Whitney U test and Cramér's V) were used for statistical analysis. Results: Overall, 77.7% of all adverts complied with legal requirements. SGM appeared in 58.1% of adverts. Warning messages occupied an average of 1.58% of the screen (SD = 0.47%), with significantly greater coverage in adverts featuring an SGM (p < 0.001). Screen coverage varied significantly across different gambling types (p < 0.001) but not across match segments (p = 0.834). Conclusion: The limited screen coverage and compliance issues identified highlight notable regulatory gaps, particularly regarding minimum size, font, and colour contrast requirements for warning messages. The simultaneous display of warnings alongside promotional content also reduces their effectiveness. Current regulations should be strengthened to better protect consumers from gambling-related harm.