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 inter-temporal 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.
Keywords: Behavioral addiction; decision-making; impulsivity; internet gaming disorder; meta-analysis; reward function.
© 2021 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.