"Good health sites are not meant to replace talking to a doctor. Rather, they help patients prepare for appointments and take more responsibility for their health."

The survey also found that the vast majority of people consider themselves highly health conscious - making them a receptive audience for health information.

Currently, 32-34% of adults aged 18 to 54 used the internet to search for health information.

This number decreases to 27% in the 55 to 64 age group, and further to 14% in the 65 and over age group.

Young internet users often conduct online health research on behalf of older family members who do not use the internet.

Audience will grow

However, Datamonitor says that the audience for health information online will grow naturally as the population ages, and more and more people grow up with the net.

It recommends that website operators focus their efforts on building a good long-term relationship with their existing consumers, rather than on attempting to attract non-internet users.

At present, general health sites and sites run by governments or institutions are more popular than those run by pharmaceutical firms, as they are perceived to be more objective.