The study's lead author, Dr Aaron Drummond of Massey University, said there had also been long-standing debate in scientific literature over the effect.
"We found an extremely small effect of violent gameplay on aggression, which in our view is too small to be practically meaningful," he said.
"More importantly, we found that high-quality studies typically had effect sizes which were statistically indistinguishable from zero, implying no significant relationship between violent gameplay and aggression in the highest quality studies.
"We also found evidence that longer time periods were associated with smaller changes in aggression suggesting that, contrary to previous suggestions, violent gameplay does not cumulatively increase aggression over time."
Taken together, Drummond said, the results strongly implied that violent games did not meaningfully increase the aggressiveness of players over time.
"We call for greater use of pre-registration practices in future work on violent video games to help reduce researcher subjectivity and increase the quality of research in this area."
Victoria University senior lecturer Dr Simon McCallum, who has taught game development for 16 years and long been involved in the industry, said the question was one that'd often been asked – and it seemed to be motivated by "fear rather than facts".
"Youth violence has decreased as game playing has increased. Large groups of computer game players spend time with each other without any violence, whereas over the weekend, schoolboys were stood down for having a punch-up after a rugby game," McCallum said.
"This sort of violence is extremely rare at computer gaming events."
He said the meta-analysis in this study backed the long-standing understanding of most people working in the game industry.
"The relationship between violence in games and aggression is so small that, as the authors cite, you would ban 'potatoes or eyeglasses' because they have stronger effect sizes.
"Much of the existing research has methodological flaws and often seems to be trying to justify an existing belief rather than reporting data. The study covers a wide range of research and does an excellent job of digging into each article to find potential bias."
But he added that many parents will still worry about content – something that age warnings helped within New Zealand.
"This study shows that young people are not likely to become more violent because of the computer games they play," McCallum said.
"Parents can be reassured that they are not terrible parents if their children have played violent video games. What we as parents should do is play games with our kids and explain fantasy versus reality.
"Having conversations about content is far more important than shielding them from content.
"Children will model the behaviours they see from people they trust, our job as parents is to be the people they trust and model the behaviours we want for our children."
