In 2012 a study was released stating that first person shooters train players to better fire real world guns. Since then the study has been examined and discrepancies uncovered. (Reviewers noticed that some of the numbers didn't match up and indicated the results had been skewed.) The university (Ohio State) who published it was notified and soon after the process to remove the study began.
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Another study trying to show games make people violent has been removed. It's great to see people push back against the idea that interactive media is somehow corrupting everything and that it's an easy scapegoat.
Dear Parents,
The reason your little darling is a violent hellspawn isn't that they played Grand Theft Auto or <other game here>. There are any number of reasons why they might be that way... From poor upbringing to mental disorders to substance abuse. So stop trying to blame the one thing that has nothing to do with your child's problems and get to the real root of the issue.