A new report from the Swedish Media Council comes to the conclusion that, while violent games may make the children that play them more aggressive, there's no conclusive evidence that "the games themselves cause kids' aggressive behavior." The Media Council is a Swedish government agency whose mission statement is to "reduce the risk of harmful media influences among minors and to empower minors as conscious media users."
The findings are based on a review of more than 100 articles about violent games and aggression which have been published in international scientific journals since 2000. The review found that there is a clear and statistically significant link between violent games and aggressive behavior. But the review also found that many of those same studies use different methods to measure aggression, and few produced a clear connection to violent behavior. Many of those same studies suffered from "serious methodological deficiencies” and didn't provide sufficient evidence to establish a causal relationship.
The studies that did attempt to examine other causes of aggression found that factors such as poor physical health or family problems were factors that lead to violent behavior and a propensity to play violent games.
The review also found that there was too little research into the theory that violent video games cause violent behavior among people with certain personality traits.
Taking all those findings into account, the Council concluded that “there is no evidence that violent computer games cause aggressive behavior”.
“If research can't provide any simple answers about how games make children aggressive, perhaps we adults should stop judging the games children play based on whether they are violent or not,” Media Council researcher Ulf Dalquist said in a statement.
On a related note, you might want to check out this PDF brought to our attention by Avalongod which says the same thing. Interestingly a review of those research studies that used gambling addiction as a jump-off point for research were found to be highly flawed for a number of reasons...
Source: Swedish Media Council