I always have my doubts about crap studies like this....No real details are given. Info on the children should be mentioned as well, do they come from divorced homes? How about homes where the parent's don't interact with the kids on much more than a "have to" basis? Where do the kids come from, an "inner city" environment or rural areas? What kind of interaction do the kids get beside playing the video games? Is there structured "family time" there or merely leaving the kids to their own devices?
More of the issue actually comes from "parents" using a device like a video game to pass for entertainment rather than actually doing something with the kid, pitching around a ball or going for walks.
There's just way too damn many variables to consider before a real valid opinion can be formed, as it stands this is little more than an "it would appear that" piece. The only thing that bugs me are people who are "against" games reading stuff like this and yelling "See!"