Cognitive distortions are inherent to disordered gambling, with most gamblers holding inaccurate beliefs about their gambling behaviour and likely outcomes. It is thought that these cognitive distortions both maintain and exacerbate disordered gambling. All gambling activities are games of chance (except poker); however, many gamblers interpret their gambling as a matter of skill, believing they have the capacity to influence the outcome of the game, creating false illusions of control [7] [8] . Such distortions lead to beliefs that gambling wins may be predicted, and result in overconfidence in hope and predictions of winning [8] .

In comparison to healthy controls, disordered gamblers have been shown to exhibit higher frequencies of erroneous gambling-related beliefs and hold a greater conviction in these beliefs. Even infrequent gamblers exhibit similar beliefs to disordered gamblers, albeit to a lesser extent [8] [9] [10] . Toneatto, Blitz-Miller, Calderwood, Dragonetti and Tsanos [11] stated that 92% of disordered gamblers held erroneous gambling-related beliefs. The authors found that disordered gamblers often exhibited behavioural patterns reflecting irrational beliefs such as; talking to Electronic Gaming Machines (EGMs), becoming angry when another patron used a favoured machine, hitting EGMs, as well as making statements indicating that the presence of others influenced their “luck” [12] .

As erroneous beliefs have been shown to play a fundamental role in the development and maintenance of gambling behaviours, cognitive approaches in the treatment of disordered gambling aim to challenge erroneous beliefs about gambling outcomes [7] [8] [11] . This is achieved through the examination of individually held beliefs, provision of factual information and restructuring of erroneous automatic thoughts [13] . Cognitive techniques are often combined with behavioural interventions such as financial management, relaxation, and systematic desensitisation, whereby gamblers are gradually exposed to gambling- related cues [13] . The combination of behavioural and cognitive techniques has been successful in reducing the frequency of gambling activities and gambling- related cognitions in disordered gamblers [14] [15] ; although a recent Cochrane review has highlighted the need for further research to measure the long term effects of these findings [16] .

Despite the successes of cognitive-behavioural treatment methods, there is evidence to suggest that approaches relying purely on cognitive interventions are also effective in reducing gambling beliefs and frequency of gambling behaviour [17] [18] [19] . For example, Ladouceur et al. [18] evaluated the efficacy of a cognitive treatment model aiming to correct erroneous beliefs around the concept of randomness, the independence of events, and control over gambling outcomes. The results indicated that the majority of the participants displayed increased control over their gambling activities and reduced their urges to gamble at six months follow-up.

This finding was replicated more recently in a randomised-controlled trial in Australia comparing the effectiveness of cognitive therapy with exposure therapy [20] . Participants were 87 individuals with moderate to severe gambling problems, as measured by the Victorian Gambling Screen. Participants were randomly allocated to either the cognitive therapy condition or the exposure therapy condition, and were eligible for up to 12 - 60-minute individual treatment sessions, taking place on a weekly basis. Cognitive therapy focused on misconceptions about gambling, such as the concept of randomness, whilst exposure therapy involved extinguishing the urge to gamble through exposure to gambling cues with response elimination. Results indicated that both cognitive therapy and exposure therapy were equally effective in reducing gambling severity symptoms from pre to post-treatment and at a 6-month follow-up. Interestingly, there were fewer drop-outs within the cognitive condition, perhaps due to the relatively confronting nature of exposure therapy.

Cognitive-behavioural and cognitive treatment methods generally take place over a period of weeks or months. Despite the successes of these methods, there is evidence to suggest that briefer cognitive interventions may be effective in reducing anxiety and fears relating to negative evaluations in social phobia, reducing the frequency and believability of negative cognitions in specific phobias, and increasing restraint and ability to manage food cravings [21] [22] .

Current literature examining the efficacy of brief cognitive interventions for disordered gambling, although limited, indicates that brief interventions may be helpful in reducing erroneous gambling-related beliefs [23] [24] [25] . Williams and Connolly [25] found that the provision of information explaining probability resulted in increased resistance to gambling fallacies; however, this increased resistance did not translate in reducing gambling behaviour. On the other hand, Floyd, Whelan and Meyers [23] found that individuals who received a brief educational intervention prior to gambling along with brief messages addressing irrational gambling beliefs whilst gambling, reported fewer irrational beliefs and took fewer risks whilst engaging in gambling activities. It is possible that the laboratory setting and presence of a researcher mayreduce the external validity of the findings. Toneatto and Gunaratnee [24] compared a brief cognitive intervention which focused on identifying and restructuring erroneous gambling cognitions, with three brief treatment programs; behavioural therapy, motivational interviewing, and a “minimal intervention” which involved a 90-minute advice-oriented feedback session coupled with the provision of a booklet of practical strategies. All four treatment programs were equally effective in reducing gambling frequency and symptom severity, with significant improvements through to twelve months post treatment [24] . This approach is important to consider in terms of the affordability and accessibility of treatment as well as managing waiting lists. Given that the current literature reflects outcomes with clinical populations, it is also proposed that brief programs may be successfully applied as preventative strategies with at-risk groups.

Whilst there is little evidence on the optimal mode of delivery for gambling interventions, Phillips and Blaszczynski [26] suggested that online treatments for disordered gambling are likely to foster increased participation due to their convenience, accessibility, privacy and cost-effectiveness. Online interventions for disordered gamblers are a relatively new treatment option and there is a lack of empirical evidence surrounding their effectiveness [27] . Despite this, there is a significant amount of research supporting the effectiveness of online interventions for other addictions including alcohol abuse and smoking [28] [29] [30] . Comparisons with face-to-face therapy revealed that online interventions for addictions are equally effective in improving client knowledge and achieving positive behavioural and clinical outcomes [27] [31] . It is clear that online interventions have an important role in the treatment of addictions; which suggests that further research regarding the efficacy of online interventions specifically designed for disordered gamblers, may be beneficial. Research by Toneatto et al. [32] indicates that individuals with mild to moderate gambling problems do not necessarily require formal interventions, suggesting that the development of online interventions may be particularly relevant to this population.

Given the extent to which erroneous cognitions have been shown to maintain the cycle of disordered gambling and the early evidence suggesting that brief interventions may be helpful, the current study investigates the impact of a brief, online educational intervention designed to reduce erroneous gambling beliefs in a non-clinical sample.

One hundred and twenty one Australian undergraduate psychology students (27 males and 94 females) aged between 17 and 69 years old (M = 24.79, SD = 11.16) were recruited to take part in an online study assessing gambling habits. As expected, mean scores for gambling severity (M = 5.01, SD = 7.94) were below the cut-off score which clinically defines disordered gambling on the Victorian Gambling Screen (VGS), indicating that the sample of participants were not a population with severe gambling problems. Participants reported low frequencies of gambling behaviour, with the majority of participants indicating that they had not gambled within the last month. Participants who did engage in gambling activities reported participation in a range of activities including electronic gaming machines, sports and horse betting, lotteries, card/table games and raffle tickets.

Participants answered basic demographic questions, provided information about their gambling behaviour in the last four weeks, and indicated their current intentions to gamble. Participants were then asked to complete the Gambling Related Cognitions Scale (GRCS) [33] and Victorian Gambling Screen (VGS) [34] . Following completion of the questionnaires, participants were randomly allocated to either an educational intervention or the alternative intervention. Both interventions required participants to read a short text about gambling. Participants were not aware that the content of these texts differed. All participants, regardless of which intervention they received, were asked to complete the GRCS for a second time, and to report their intentions to gamble. This process took approximately 30 minutes to complete.

Victorian Gambling Screen (VGS). The VGS [34] , is a self-report questionnaire containing 21 items and three subscales; harm-to-self, harm-to-others, and enjoyment of gambling. Despite the usefulness of the latter two scales, validation studies indicate they do not meaningfully identify disordered gamblers; therefore, the 15-item harm-to-self scale (α = 0.89) was used in this study [13] [35] . Items are scored on a five point Likert scale ranging from 0 (never) to 4 (always). Scores can range from 0 - 60, with scores of 21 or above indicating disordered gambling.

Gambling Related Cognitions Scale (GRCS). The GRCS [33] is a self-report questionnaire designed to assess erroneous thoughts about gambling, and demonstrates good internal consistency (α = 0.93) in non-clinical populations. The GRCS contains 23 items whereby participants indicate the extent to which they agree with each statement on a seven-point Likert scale ranging from 0 (strongly disagree) to 6 (strongly agree) with higher scores indicating more erroneous beliefs about gambling.

Educational Intervention. The educational intervention involved participants reading a short text about gambling. The intervention was designed to target erroneous beliefs about gambling and included information specifically challenging beliefs about chance, luck and control. The text was taken from a disordered gambling treatment manual [8] . The text was modified slightly in order to increase relevance to an Australian population.

Alternative Intervention. The alternative intervention also involved participants reading a short passage about gambling. The passage provided informative factual information about gambling prevalence and types in Australia. This passage was designed to be interesting to readers, yet was worded such that the information was neutral and did not provide support for either pro or anti-gambling perspectives. The information for this intervention was drawn from a gambling report publicly available on the website of the Australian Psychological Society [36] .

Two bivariate linear regression analyses were conducted in order to determine whether gambling severity and intentions to gamble could be predicted from gambling-related cognitions. Gambling-related cognitions predicted intentions to gamble, R² = 0.26, F(1, 119) = 43.08, p < 0.001, and gambling severity, R² = 0.39, F(1, 119) = 75.99, p < 0.001.

Two independent samples t-tests were conducted to compare the change in cognitions and intentions to gamble between the educational and alternative interventions. The education group had significantly fewer gambling-related cognitions (M = −8.39, SD = 13.54) than the group receiving the alternative intervention (M = −4.38, SD = 8.28); t(119) = 2.02, p = 0.046, two-tailed, Cohensd = 0.3. There was no significant differences between the educational (M = −0.04, SD = 0.15) and alternative (M = −0.03, SD = 0.09) interventions in terms of intentions to gamble; t(119) = −0.52, p = 0.607, two-tailed.

A hierarchical multiple regression was conducted to determine whether gambling severity moderated the relationship between the educational intervention and change in gambling-related cognitions. The educational intervention was more effective in reducing gambling-related cognitions in those with more severe gambling behaviours. Individuals displaying more severe gambling behaviours were more likely to benefit from the educational intervention. Regression equations can be found in Table 2.

An interaction plot for intervention, gambling severity and change in cognitions can be found in Figure 1. Examination of the interaction plot indicated that the educational intervention was more effective in reducing gambling-re- lated cognitions than was the alternative intervention, and that the effectiveness of the educational intervention in reducing these beliefs increased as gambling severity increased. Mean change in cognition scores for the alternative intervention remained similar regardless of the level of gambling severity.

*p < 0.05, p < 0.01, ***p < 0.001 (2-tailed).