A researcher at Sheffield Hallam University has found that social-networking sites such as Facebook, Bebo and MySpace do not lead to closer friendships.

Facebook has attracted around 34 million users and MySpace has more than 200 million. The Sheffield study found that although making friends on such sites increases the number of people you are in contact with, it does not mean the friendships are genuine. Dr Will Reader, who carried out the study, has put this in part down to the fact that it is very easy to be deceptive on the internet.

Dr Reader's team asked more than 200 people to fill in questionnaires about their online networking habits. He asked them to say how many online friends they had, judge how close they were and if they had met face-to-face. He found that 90 percent of those regarded as close contacts were people who had met face-to-face.

During the British Festival of Science at York University, Reader commented on his findings and said that forming and maintaining social networks is easier using such sites because we can post information to multiple people. He also said we need to be able to see another person is trustworthy and is going to invest in us and be there for us to develop real friendships. This is not always possible online.

At the Festival Dr Reader said that sites such as Facebook have made it a case of quantity rather than quality of friendships.

The study has seen that of the average group of 150 friends a Facebook or MySpace user has only 5 close personal friends will be contacted regularly. Dr Reader has suggested this may be because it is hard to keep track of very large numbers of friends. Another of his findings was that 90 percent of the contacts study participants regarded as close friends were made face-to-face.