Objective: Some gambling product messages are designed to inform gamblers about the long-run cost of gambling, for example, "this game has an average percentage payout of 90%." This message is in the "return-to-player" format and is meant to convey that for every £100 bet about £90 will be paid out in prizes. Some previous research has found that restating this information in the "house-edge" format, for example, "this game keeps 10% of all money bet on average," is better understood by gamblers and reduces gamblers' perceived chances of winning. Here we additionally test another potential risk communication improvement: A "volatility statement" highlighting that return-to-player and house-edge percentages are long-run statistical averages, which may not be experienced in any short period of gambling.
Method: Gambling information format and volatility statement presence were manipulated in an online experiment involving 2,025 U.K. gamblers.
Results: The house-edge format and the presence of volatility statements both additively reduced gamblers' perceived chances of winning. In terms of gamblers' understanding, house-edge messages were understood the best, but no consistent effect of volatility statements was observed.
Conclusions: The return-to-player gambling messages in current widespread use can be improved by switching to the house-edge format and via the addition of a volatility statement. (PsycInfo Database Record (c) 2022 APA, all rights reserved).