Most doctors use computers, but for the majority their use is restricted to routine administration such as billing health providers. Almost all GPs are networked within their practice, but few systems go beyond. Those that do are mostly using the network to get pathology test reports from their local hospitals.

"That's just faster data, not knowledge management," says Don Detmer, a former surgeon who now studies healthcare systems at Cambridge University.

However, he believes the scales are poised to tip in favour of systems that will revolutionise the delivery of healthcare and dramatically improve the way patients are treated. The internet is likely to revolutionise the way GPs use information over the next three years, vastly increasing the success of current treatments.

Only about 10 per cent of GPs ever search the literature to help them treat their patients. Almost all say they face unanswered questions and when provided with relevant information, 80 per cent will act on it, and change their care of the patients in question.

"The internet hasn't hit yet," says Prof Detmer. "But we've reached tip factor." Two factors are driving the change: Pressure from governments to practice evidence-based medicine means doctors know they can no longer afford simply to ignore the incredible volume of medical information published, even if they cannot actually deal with it.

Meanwhile, web-enabled systems and client-server IT architectures are challenging traditional software for the first time, giving real-time clinical guidance, access to patient records and potentially linking doctors with colleagues worldwide.

"If we ran airlines like we run hospitals none of us would fly, not because people are bad but because medicine is complex. The knowledge explosion is outstripping anyone's capacity to know what they need to know," says Prof Detmer.

Overload

Medicine is about complex decision-making and most diagnosis relies on a balance of probabilities. About 2m pieces of new medical information are added to the literature every year, but humans can only usually use three or four variables. There is just too much information out there.

"The question is: how do you embed process management into a computer system that makes you as good as you can be," says Prof Detmer. What doctors need is fast access to fairly simple information. "I don't need expert systems," says Prof Detmer. "I need simple systems that stop me doing dumb things."

A number of companies have seized on this fact to put information into what Prof Detmer calls "just in time knowledge".

In the UK, South Norfolk Primary Care group is using WAX info's ActiveLibrary in 75 practices across the county. The system uses a browser adapted to create virtual libraries of e-books.

In the US, Unbound Medicine and Up To Date.com are introducing hand-held and internet technologies to provide doctors with answers to medical questions, wherever and whenever they are needed. These subscription services use integrated palm and web-based platforms to provide drug prescribing data and information from medical journals by the bedside.

OnMedica, a UK company, has combined a clinical information service with e-business services for pharmaceutical companies. Electronic patient records also offer significant time savings, freeing up doctors to spend more time actually treating people. Electronic records could also allow health providers to get a much more accurate picture of what treatments work best for whom, and possibly even tailor their advice to take account of regional differences.

"In the not too distant future GPs will have electronic patient records that can automatically look for latest advice from Nice [the UK's National Institute for Clinical Excellence] or warnings on drugs," says Andrew Burnett, a former doctor working for KPMG Consulting. "The technology exists. The limiting factor is bandwidth available to the doctors' desktops."

Consultations

Human resistance is also a factor. Only about 12 per cent of doctors have gone over to paperless consultations, but the figure is rising. Most blame experience with earlier systems. "The old IT was pretty clunky, pretty brutal as a matter of fact," says Prof Detmer. "But increasingly technology is less and less the issue."

US healthcare providers, such as Kaiser Permanente in Northern California, have invested an enormous amount in electronic records that seamlessly integrate GPs, specialists and payers. Penetration has been much slower in Europe, where governments have yet to provide funding. "It is like building airliners, a huge front-end investment," says Prof Detmer.

In the UK, electronic records are most widespread among out-of-hours co-operatives, where doctors need to send copies of records to patients' own GPs. The electronic records replace the practice of faxing or simply leaving notes with the patient to pass on.

Dr Burnett says if out-of-hours services, NHS Direct and accident and emergency departments could share all their records it would cut the amount of form filling - and the number of times patients must answer the same questions - by a factor of seven.

In Yorkshire, the Pinderfields and Pontefract Trust is piloting a Novell platform that allows GPs to book surgery online. Eventually, the trust wants to put all its records into an electronic format.

Com Medica, a spin off from Imperial College in London, is one of some 250 companies integrating patient records with medical images. Richard Kidney, chief executive, says speed is critical to acceptance.

The Com Medica system, which is used by St Mary's Hospital, London, takes about four seconds to bring up a chest X-ray on a standard PC. So far it is being bought by hospitals and installed on their intranets. But Dr Kidney says it could be used on any PC as long as it had a web browser.

The internet is increasingly driving patients' expectations of computerised records.

Patients with net access are starting to ask for access to their records via secure sites. Prof Detmer believes this will make people more involved in their care. "Right now most people know more about their car from the dashboard dials than they do about their own health," he says.