A study of 445 Internet users by the University of Hertfordshire found that women were equally likely to define themselves as addicts as men.

Most addicts were around 30 years old.

Some 40 million people in the USA are estimated to be regular users of the Internet, compared with around seven million in the UK.

In the early days, most users were male, but women are fast catching up.

A 1994 US survey found that only 5% of users were female. By 1998, the numbers had risen to 38.7%.

Stereotypes

The researchers, who presented their findings to a British Psychological Society conference in London on Tuesday, said: "A stereotype has developed that 'the typical addict is a teenager, usually male, with little or no social life or no self confidence' although initial research does not necessarily support such a view."

They added a note of caution about their findings, however, saying the male/female ratio could be due to the rising number of female users and the fact that women were more likely to volunteer for this kind of research.

There is still some debate about whether people can be addicted to the internet and how addiction is defined.

Some studies suggest it is more likely that people with addictive personalities are drawn to the Internet than that the internet itself generates addiction.

Shy

The University of Hertfordshire researchers allowed users to define themselves as addicts. Forty-six per cent said they had an addiction.

They were asked how often they used the net and their attitude to it. Addicts were defined as those who used the Internet a lot and were very positive about it.

Women were more likely than men to score high on the addiction rating.