Loot box engagement: A scoping review of primary studies on prevalence and association with problematic gaming and gambling.

Background: Loot boxes are an increasingly common type of random microtransaction in videogames. There is some concern about their expansion and entailed risks, especially among adolescents. The actual prevalence of engagement with loot boxes among child and adult population is uncertain, and there is still controversy over the nature of their relationship with problematic gaming and gambling.

Objectives: The aims of this scoping review are to summarize the characteristics and findings of published primary empirical studies about the prevalence of engagement with loot boxes and/or their relationship with problematic gaming and gambling, taking in account the type of sample, time frame and measured variables.

Methods: This study follows the Joanna Briggs Institute's "Guidance for conducting systematic scoping reviews" and the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Three academic databases provided 299 articles.

Results: Sixteen primary empirical studies met the inclusion criteria for this review. All studies used cross-sectional designs, and most used convenience samples. Twelve study samples were comprised exclusively of gamers, and two were comprised of gamers and/or gamblers. Only six studies included adolescents. The annual prevalence rate of loot box purchases was higher for adult gamers than for adolescents (22.7%-44.2% and 20%-33.9%, respectively), but in studies with general population samples, the opposite was true (24.9% for players aged 13-14 versus 7.8% for adults). In general, the studies suggested a significant positive relationship between engagement with loot boxes and problematic gaming and gambling, but this may be related to the type of engagement (open/purchase/sell), and the characteristics of the study participants (male/female, adolescents/adults, gamers/gamers-gamblers/general population).

Conclusions: This scoping review summarizes the results of recent empirical studies on engagement with loot boxes and discusses how methodological issues may affect their results and interpretation. Recommendations for future research are also provided.