Children who play video games are more likely to think and act in aggressive ways, according to a three-year study of more than 3,000 school kids.
Frequent use of video games was also linked to higher rates of aggressive behaviour and thoughts, according to the survey.
Answers were similar among boys and girls, and parental involvement wasn't likely to change behaviour.
The researchers said their findings support previous research that's shown a link between video games and aggression.
"Habitual violent video game playing increases long-term aggressive behaviour," the authors concluded.
The kids, all of whom went to school in Singapore and had an average age of 11, were asked to respond to six questions about aggressive behaviour.
Questions included, "When someone has angered or provoked me in some way, I have reacted by hitting that person."
Responses were given on a scale of one to four, ranging from "strongly disagree" to strongly agree."
Three questions on hostile thoughts were included, such as, "Suppose a boy says something bad to another boy John. Is it wrong for John to hit him?" Answers were also given on a four-point scale, from "really wrong" to "perfectly okay."
But other experts have questioned the use of self-reported answers in the survey and say the study doesn't prove that violent video games cause aggressive behaviour.
"This study shows an association, of unclear magnitude, of violent video game-playing with subsequent aggressive behaviour," said David Spiegelhalter, a professor at the University of Cambridge, who was not involved in the study.
"It does not, and cannot, show that the association is causal."
The research was published in the JAMA Pediatrics journal.
