Background: Participation in Internet gambling is growing rapidly, as is concern about its possible effects on the public's health. This article reports the results of the first prospective longitudinal study of actual Internet casino gambling behaviour.
Methods: Data include 2 years of recorded Internet betting activity by a cohort of gamblers who subscribed to an Internet gambling service during February 2005. We examined computer records of each transaction and transformed them into measures of gambling involvement. The sample included 4222 gamblers who played casino games.
Results: The median betting behaviour was to play casino games once every 2 weeks during a period of 9 months. Subscribers placed a median of 49 bets of euro4 each playing day. Subscribers lost a median of 5.5% of total monies wagered. We determined a group of heavily involved bettors whose activity exceeded that of 95% of the sample; these players bet every fifth day during 17.5 months. On each playing day, these most involved bettors placed a median of 188 bets of euro25. Their median percent of wagers lost, 2.5%, was smaller than that lost by the total sample.
Conclusion: Our findings suggest that Internet casino betting behaviour results in modest costs for most players, while some, roughly 5%, have larger losses. The findings also show the need to consider time spent as a marker of disordered gambling. These findings provide the evidence to steer public health debates away from speculation and toward the creation of empirically-based strategies to protect the public health.