Cost-of-play information and volatility warnings may be useful in helping reduce gambling-related harm. Cost-of-play information can be provided on electronic gambling machines in a “return-to-player” or a “house-edge” format. This study was an experiment to examine whether people who gamble would play fewer spins on a slot machine when given: (1) house-edge information instead of return-to-player information; (2) a volatility warning; and (3) a total amount bet counter. US-based participants over 18 years of age were recruited using Prolific Academic. Participants had to have prior experience in gambling. Participants received a bonus of $3.00 if they completed an initial captcha retyping task. They could then choose to either keep the money or use it to play on a simulated slot machine. Participants who were shown house-edge information instead of return-to-player information played fewer spins on the slot machine. Similarly, participants who were shown a volatility warning played fewer spins than those who were not. Participants with higher risk of problem gambling played more spins. The success of house-edge information and volatility warning did not differ across participants based on their problem gambling severity.
