Reward-related Decision-making Deficits in Internet Gaming Disorder: A Systematic Review and Meta-analysis.

AIMS To estimate the aggregated effect sizes of reward-related decision-making deficits in internet gaming disorder (IGD) and to explore potential moderators on the variability of effect sizes across studies. DESIGN Review of peer-reviewed studies comparing reward-related decision-making performance between IGD and control participants identified via PubMed, Web of Science, and ProQuest databases. Random-effects modeling was conducted using Hedge's g as the effect size (ES). The effects of decision-making situation, valence, sample type, testing environment, IGD severity, and self-reported impulsivity on decision-making differences were examined by moderator analyses. SETTING No restrictions on location. PARTICIPANTS Twenty-four studies (20 independent samples) were included in the meta-analysis, resulting in 604 IGD and 641 control participants and 35 ESs. MEASURES Reward-related decision-making differences between IGD and control groups. FINDINGS The overall ES for decision-making deficits in IGD was small (g = -0.45, p < 0.01). The effects were comparable across risky, ambiguous, and intertemporal decision-making. Larger aggregate ESs were identified for pure-gain and mixed compared with pure-loss decision-making. Studies based on clinical and community samples showed similar effects. No significant difference between behavioral studies and those with extra measurements was observed. Decision-making alterations were not closely associated with IGD severity or self-reported impulsivity differences at the study level. CONCLUSIONS Internet gaming disorder appears to be consistently associated with reward-related decision-making deficits.