In a letter to the Commons Health Select Committee, 23 professors raised questions about the system, its progress and whether it will work.

The concerns were brushed aside by the Department of Health but are an index of growing doubts about the system, called Connecting for Health, which is designed to allow instant access to patient records and for patients to make appointments with consultants online from GP surgeries.

The letter, reported in Computer Weekly, amounts to the most heavyweight challenge yet to the programme, announced four years ago by the Prime Minister.

Connecting for Health, previously known as the National Programme for Information Technology (NPfIT), will link more than 30,000 GPs in England to 300 hospitals by 2012.

It involves an online booking system, a centralised medical records system for 50 million patients, e-prescriptions and fast computer network links between NHS organisations.

The academics’ letter, signed by professors from Oxford, Cambridge, the London School of Economics, Edinburgh, Birmingham, York and many other departments, says that the project has been managed in a secretive way.

“Concrete, objective information about NPfIT’s progress is not available to external observers,” it says. “Reliable sources within NPfIT have raised concerns about the technology. We suggest an assessment should ask challenging questions and issue concrete recommendations.”

Concerns have been heightened by a delayed report from the National Audit Office, that was expected last summer and will not be published until this summer at the earliest.

“My instinct is that had they had anything good to say about it it would not have been delayed so long,” said Martyn Thomas, a computer consultant and a visiting professor at Oxford University, who is one of the signatories. “In this case there has been a lot of pressure and a political timetable set by ministers from outside. There has not been enough scrutiny.”

He said that the UK Computing Research Committee, an 80-strong expert group, had offered to help, but nobody from NPfIT had been interested in talking to them.

The Department of Health responded: “The National Programme for IT is under constant review, scrutiny and audit by Parliament and government bodies. We remain confident that the technical architecture is appropriate and will enable benefits to be delivered for patients, whilst ensuring value for money to the taxpayer.”

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