I think peer review is a very basic hurdle in the research process. The results are then up for review - and that's what we're doing here in a minor way. In the section that really matters, violent behaviour, results seem massively skewed in favour of results from cross-sectional studies. Experimental and longitudinal studies showed strong sex differences. All non-experimental (and no doubt some of the experimental) studies were strongly subject to self-selection. None of the longitudinal studies were done on subjects over 16. Just because its a meta-study doesn't mean it isn't subject to massive flaws.

Does anything in there reliably address the issue of correlation versus causation. Most people play video games - if I was a violent person surely that would be my entertainment of choice right?