Online sports gambling involvement is discontinuous in nature, with small groups of highly involved gamblers exhibiting betting behavior that is distinctly greater than other gamblers. There is some question about whether these groups, defined by exceedingly high levels of play, also have equivalently high rates of gambling problems, and whether they maintain these play levels over time. The current study builds on past work by examining the long-term trajectories of play and voluntary self-exclusion patterns across two years among a cohort of 32,262 highly-involved and less-involved online sports gamblers. We also examine the relative importance of betting behavior change as a risk factor for gambling problems by testing whether high involvement as compared to escalation of involvement is a better predictor of future self-exclusion. Measures included betting activities, transactional activities, and self-exclusion activities on a European online betting platform between February 2015 and January 2017. Results showed that bettors who were most highly involved in the first 8 months of the study in terms of number of bets and net loss were more likely to continue gambling on the platform in months 9–24 than others. Bettors who were most highly involved in the first 8 months of the study in terms of net loss and amount wagered were more likely to use self-exclusion than others, and more likely to have multiple self-exclusions. Escalations in frequency of play and average bet size within the first 8 months emerged as significant predictors of self-exclusion, even when controlling for high involvement.
