Part of the problem, Griffiths argued, is that the new work may be measuring preoccupation instead of addiction.

In the study, teachers handed out questionnaires to students in the third, fourth, seventh and eighth grades, including questions about their gaming habits, social skills, school performance and depression.

The kids also answered ten questions to find out if they were addicted to gaming - so-called “pathological” gamers. If they answered half in the positive, they got the label.

The questions included things like having neglected household chores to spend more time on video games, doing poorly on a school assignment or test as a result, or playing video games to escape from problems or bad feelings.

On average, the kids said they played about 20 hours a week. Between 9 and 12 percent of boys qualified as addicted in this study, compared to 3 to 5 percent of girls.

Of those children who started out as addicts, more than eight in 10 remained so during the study. “It’s not simply a short-term problem for most children,” Gentile said.

While the researchers didn’t put a number on how many youngsters had mental problems, they did find that those who played longer hours, were more impulsive or had poorer social skills were at higher risk of getting “addicted” over the 2-year period.

Those who did become addicted reported increasing symptoms of depression, anxiety and social phobia.

Gentile said it appeared that unhealthy gaming habits were fueling the kids’ mental problems, which then in turn might cause them to up their screen time and so forth. But he acknowledged his research didn’t prove that point.