A new study of online gamers has revealed that about 12% show signs of addiction to playing videogames.

The wide-ranging study asked around 7000 gamers who volunteered to take part in the survey about their gaming habits in a series of two online questionnaires. The sample averaged 21 years of age, and was comprised of 94% males.

One in nine of them, or around 840, responded in such a way that showed they had at least three signs of dependence on gaming; the criteria of dependence syndrome was based on key symptoms outlined by the World Health Organization.

This means that 12% showed signs of craving, tolerance, withdrawal symptoms, loss of control, neglect of other activities, and other "negative consequences". In a comparison with other gamers in the survey, those that displayed addicted behaviour played for significantly longer periods.

However, Professor Ralf Thalemann of the University Medicine Berlin who carried out the study said, "Although these gamers show some signs of addiction normally found in other more traditional addictions, our results do not conclusively show that the gamers are genuinely addicted".

"Many gamers play excessively and display few negative consequences. However, the 24-hour a day never-ending online games may provide a potentially addictive medium for those with a predisposition for excessive game playing."

Part of Professor Griffiths' thesis, which will be published in CyberPsychology and Behaviour, is that excessive gaming isn't necessarily a bad thing, and that it depends on the context of the gamers' life.