New research released on Monday conclusively links violent video game play aggression in kids.

Iowa State's psychology professor Craig Anderson analyzed 130 studies on more that 130,000 subjects worldwide, concluding that exposure to violent video games makes more aggressive, less caring kids -- regardless of their age, sex or culture.

We can now say with utmost confidence that regardless of research method -- that is experimental, correlational, or longitudinal -- and regardless of the cultures tested in this study [East and West], you get the same effects, said Anderson, who is directs the school's Center for the Study of Violence.

And the effects are that exposure to violent video games increases the likelihood of aggressive behavior in both short-term and long-term contexts. Such exposure also increases aggressive thinking and aggressive affect, and decreases prosocial behavior.

But Christopher Ferguson, an associate professor at Texas A&M International University in Laredo, says the effects are generally very low, adding that the research contains numerous flaws.

Ferguson says his own study of 603 predominantly Hispanic young people, published last year in The Journal of Pediatrics.

In it he found delinquent peer influences, antisocial personality traits, depression, and parents/guardians who use psychological abuse were consistent risk factors for youth violence and aggression.

But he also found that neighborhood quality, parents' domestic violence and exposure to violent TV or video games were not predictive of youth violence and aggression.

Anderson said the effects he is describing were not big, but not trivial in size either.

It is one risk factor for future aggression and other sort of negative outcomes. And it's a risk factor that's easy for an individual parent to deal with -- at least, easier than changing most other known risk factors for aggression and violence, such as poverty or one's genetic structure.

Both Anderson and Ferguson detail their studies in March 2010 issue of the Psychological Bulletin, an American Psychological Association journal.