Objectives:
The purpose of the present study was to validate the Polish version of the Internet Gaming Disorder–20 (IGD-20) Test that is consistent with DSM–5 diagnostic criteria.

Methods:
A total of 652 game players took part in the validation study. Confirmatory factor analysis was used to check the scale structure. Questionnaires measuring symptoms of psychopathology and desire thinking were used to estimate construct validity of the IGD–20. The analysis also considered the game genres most frequently chosen by players.

Results:
Confirmatory factor analysis confirmed a5-factor structure of the Polish version of IGD–20 questionnaire, which is consistent with previous findings in other language versions. Fit indices were evaluated collectively, indicating that the model has agood fit: χ2(142)=690.059; p <0.001; RMSEA=0.077 (90% CI: 0.071–0.083); CFI =0.950; TLI=0.940; SMRR =0.053. Internal consistency is high (McDonald’s ω =0.93). Analysis also showed significant correlations between problem gaming, symptoms of psychopathology, and desire thinking. Participants reported that they spent the least amount of time playing educational games, compared to other game genres; the frequency of educational games selection negatively correlated with the intensity of problematic gaming symptoms.

Conclusions:
The validation study of the Polish version of the IGD–20 questionnaire has confirmed the good psychometric properties of the tool and its internal structure. Further research should focus on examination of gender differences and psychometric properties in the clinical sample of players.