This study was aimed at developing a scale to determine the level of addiction to online gambling. For the study, a draft scale with 57 items related to online gambling addiction was prepared, and ten experts evaluated it for content validity. A candidate scale consisting of 28 items with a content validity index (CVI) of
0.893 was obtained. The study was completed with 650 participants in total. Cronbach’s alpha value was calculated as 0.920 for the reliability analysis. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used for the validity analysis. The three-factor and 26-item structure obtained with EFA was confirmed by CFA. With a few minor modifications, the final structure consisting of 3 factors and 21 items was obtained. In conclusion, the Online Gambling Addiction Scale (OGAS) is a valid and reliable scale consisting of 21 items and 3 sub-dimensions.

Keywords: Gambling, gambling addiction, online gambling addiction, addiction, validity, reliability