Validation of the Internet Gaming Disorder Questionnaire in a Sample of Adult German-Speaking Internet Gamers

With the inclusion of Internet Gaming Disorder (IGD) in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders comes the need for a reliable and valid questionnaire to assess the diagnosis. The Internet Gaming Disorder Questionnaire (IGDQ) is a short tool that measures IGD. Our study aimed at investigating its psychometric properties in a sample of German gamers. Eight hundred ninety-four Internet game players (mean age: 26.5 ± 8.5 years, range: 18-75 years, 87.36% male) completed an online version of the IGDQ and the Compulsive Internet Use Scale (CIUS) and provided information on their Internet and gaming use. Item and reliability analyses were computed. To investigate the component structure, the sample was randomly divided into two subsamples. A maximum likelihood factor analysis was conducted for one subsample and a confirmatory factor analysis (CFA) for the other subsample. The IGDQ had a Cronbach's alpha of 0.70. The IGDQ score correlated with the CIUS score (r = 0.59) and the time spent playing (r = 0.24). The maximum likelihood factor analysis extracted one component, explaining 30.26% of the variance, which was confirmed by the CFA. The correlation of the IGDQ score with the CIUS score is a first indicator that the IGDQ allows for valid interpretations. In all, 7.94% of the gamers met the criteria for IGD.

Using two web-based addiction Stroops to measure the attentional bias in adults with Internet Gaming Disorder

Background and aims People with substance abuse and pathological gamblers show an attentional bias. In a laboratory setting, we found an attentional bias using an addiction Stroop in adults with Internet Gaming Disorder (IGD). We aimed at investigating this effect using two web-based experiments. Methods Study 1: Gamers with IGD, casual gamers, and non-gamers (N = 81, 28.1 ± 7.8 years) completed a web-based addiction Stroop with a fully randomized word order. They saw computer-related and neutral words in four colors and indicated the word color via keypress. Study 2: Gamers with IGD, casual gamers, and non-gamers (N = 87, 23.4 ± 5.1 years) completed a web-based addiction Stroop and a classical Stroop (incongruent color and neutral words), which both had a block design. We expected that in both studies, only the gamers with IGD would react more slowly to computer-related words in the addiction Stroop. All groups were expected to react more slowly to incongruent color words in the classical Stroop. Results In neither study did the gamers with IGD differ in their reaction times to computer-related words compared to neutral words. In Study 2, all groups reacted more slowly to incongruent color words than to neutral words confirming the validity of the online reaction time assessment. Discussion Gamers with IGD did not show a significant attentional bias. IGD may differ from substance abuse and pathological gambling in this respect; alternatively experimenting on the Internet may have introduced error variance that made it harder to detect a bias.