Measuring Risky Loot Box Use: An Item Response Theory Analysis of the Risky Loot Box Index Among Adolescents

Objective: Loot boxes (LBs) are virtual items embedded within video games that contain randomly generated in-game prizes. LB use can become risky, so it is important to have good measurement instruments, especially among adolescents, who are particularly involved in video gaming and LB purchasing. The present study analyses the adequacy of the Risky Loot Box Index (RLI; Brooks & Clark, 2019) by applying item response theory (IRT). Method: Participants were 2,443 (59% males, mean age = 16.48, SD = 1.22) Italian high school students. Results: The 2PL logistic model was applied. Item properties (i.e., severity and discrimination) were consistent with the aim of efficiently measuring risky LB use. The test information function indicated that the instrument was adequately informative. The RLI appeared to be invariant across gender, with male adolescents more at-risk than female adolescents. LB engagement was also found to explain latent trait of risky LB use over and beyond video gaming and gambling frequency and severity when controlling for gender. Conclusions: The RLI is an efficient screening tool that can specifically measure risky LB use among youth. It can profitably be used for research and intervention purposes. The promising usefulness of the IRT score for clinical purposes is also discussed.