Fears that a £2.3bn scheme to computerise huge sections of the NHS could descend into chaos have prompted the Government's spending watchdog to take the unusual step of reviewing the scheme at its start.

The National Audit Office confirmed yesterday that it has already contacted the Department of Health to investigate the scheme, which will bring wide-ranging changes to technology used every day in the health service. Normally, the NAO only begins such investigations once projects have been implemented. It freq-uently identifies faults, sometimes on a massive scale.

Unusually, the NAO is questioning the managers of the project very early in its life.

The shortlists for the main bidders were announced last week, and the first major implementation of the scheme is not expected until 2005. The inquiry has been prompted by concerns expressed by some of the NHS's 100,000 clinicians, who will be affected by the change, and industry observers who fear that the project has the potential to turn into a fiasco comparable with those seen at the Inland Revenue and the Passport Office.

The £2.3bn NHS computerisation scheme will introduce the electronic booking of appointments at hospitals and GP surgeries, electronic patient records, "e-prescriptions" that would be sent direct to pharmacists and new interlinked computer systems to support the improvements.

Many of those who will be directly affected are doctors, but last month a survey found that only 20 per cent had been consulted over the changes.

The NAO's investigation is reported today in Computer Weekly magazine, which notes that the NAO could produce a report on its early findings for Parliament - though this would be a "preliminary step".

The NAO told Computer Weekly: "We have asked the Department [of Health] to demonstrate to us how it has incorporated the lessons drawn from earlier projects."

Charles Hughes, director of eManagement, a consultancy specialising in the public sector, welcomed the early involvement of the NAO.

He said: "The NAO's reports open up issues that other projects should take on board. But they're always retrospective, and the information they contain would have been helpful to the program it reports on earlier."

He noted that the overall success of the project would partly depend on involving the clinicians who would have to use the new technology daily. "It's quite easy to implement an IT project quickly, but that doesn't mean it's successful," Mr Hughes said. "You have to educate and train them [the clinicians] too."

One of the biggest problems confronting the NHS at present is the wide disparity in technology use between hospitals and even individual clinicians within the same hospital. "Some are very advanced, and some are still using paper and pencil," Mr Hughes said.

Early concerns have also been expressed at the way the new underlying computer systems will be administered. Rather than being owned and operated by the hospitals, they will be "outsourced" to private-sector suppliers, who will run them on behalf of the NHS.

Some industry observers have raised questions over the security and efficiency of this approach. But the Department of Health is not prepared to change its plans on the organisation of the project, whose first contracts will be awarded by the end of the year.