Personally, I'm not worried.
Has anyone ever actually participated in this kind of researches? I have..
And I can tell you that according to these kind of tests, I have every possible mental disorder known to man (including schizophrania, multipersonality disorder, passive-aggressive behavior, ADD, among other things), and I am apparently addicted to every substance known to man as well. Yes, I have tried them. The symptoms are so varied and general that everyone are bound to have some no matter what you do. It's not exactly credible when taken so out of context like this.

With that said, I feel that yes, gaming can be a real addiction on some people in a sense that they can be so invested in it that they will forsake real responsibilities. But unlike real addictions, I do not believe that gaming addiction is caused by stimulus-induced chemical imbalance, which to me is the real line in being "addicted" to something.