The issue of potential media effects on psychological health of youth and young adults has been debated for decades. Research on media effects has not always been consistent. One issue that has been raised regards whether the relatively modest media effects found in some research might be explained through mediating personality variables. This hypothesis was examined in three samples of young adults: Mexican-Americans (n = 232), Croatians (n = 455) and English (n = 150). Results indicated that trait aggression was a consistent predictor of both violent crimes and depression across samples. General personality variables were less consistent predictors of violence. although neuroticism consistently predicted depression across samples. Media violence exposure did not predict negative outcomes except among Croatians for whom exposure to violent video games predicted fewer violent crimes, and exposure to television violence predicted increased violent crimes. (C) 2011 Elsevier Ltd. All rights reserved.