Further delays can be expected to the Government's multi-billion-pound scheme to computerise medical records, a group of MPs said today.
Recent progress in implementing the new care records system across the NHS has been "very disappointing," they said.
The National Programme for IT (NPfIT), which will cost more than £12 billion, is designed to link more than 30,000 GPs to nearly 300 hospitals.
The new service will provide an online booking system (Choose and Book), a centralised medical records system for 50 million patients, e-prescriptions and fast computer network links between NHS organisations.
The medical records system means select information - such as a patient's current drugs, allergies and long-term conditions - can be shared among health professionals in England.
The Government believes this will benefit patient care and could prove vital in an emergency and, over time, more details will be added to the records.
Today, the Commons Public Accounts Committee (PAC) said there had been just six deployments of the new care records system in the NHS in the first five months of 2008/09.
It warned that further delays could be expected beyond the original 2010 target completion date.
And it said the termination of a contract with key supplier Fujitsu last May, after months of wrangling over the terms, will be having an impact.
Fujitsu was installing the programme in the south of England and its departure followed that of Accenture in 2006, which was delivering the system in the north.
The PAC report said: "The completion date of 2014-15, four years later than originally planned, was forecast before the termination of Fujitsu's contract and must now be in doubt.
"The arrangements for the south have still not been resolved.
"The Department of Health and the NHS are working with suppliers and should update the deployment timetables.
"Given the level of interest in the programme, the Department should publish an annual report of progress against the timetables and revised forecasts."
The report also highlighted other concerns, including that the programme "is not providing value for money at present" and the estimated £3.6 billion of local costs remains "unreliable".
It also highlighted how there is "some way to go" to ensure NHS staff fully support the programme and that "patients and doctors have understandable concerns about data security".
Smartcards are needed to access patient records online but there have been reports of staff sharing them, thereby breaching patient confidentiality.
The report said: "However extensive the care record guarantee and other security provisions being put in place are, ultimately data security and confidentiality rely on the actions of individual members of NHS staff in handling care records and other patient data.
"To help provide assurance, the Department and the NHS should set out clearly the disciplinary sanctions that will apply in the event that staff breach security procedures, and they should report on their enforcement of them.
"The Department does not have a full picture of data security across the NHS as trusts and Strategic Health Authorities are required to report only the most serious incidents to the Department.
"The Department's view is that it is not practical for it to collect details of all security breaches but at present it can offer little reassurance about the nature and extent of lower-level breaches that may be taking place."
Edward Leigh, PAC chairman and Tory MP, said: "The risks to the successful delivery of the National Programme for IT are as serious as ever.
"Essential systems are late or, when deployed, do not meet expectations of clinical staff; estimates of local costs are still very unreliable; and, despite action to secure their commitment, many NHS staff remain unenthusiastic.
"It is also worrying that, if trusts decide not to deploy the patient care records systems, the taxpayer can still be obliged to make payments to the suppliers concerned.
"The original aim was for the systems to be fully implemented by 2010.
"The truth is that, while some are complete or well advanced, the major ones such as the care records systems are way off the pace."
Today's PAC report is its second on the NPfIT.
Shadow health minister Stephen O'Brien said: "This is another scathing account of Labour's incompetence over the NHS IT programme.
"It highlights the lack of delivery, and the problems in the rare cases where systems have been delivered; the unreliability of the cost estimates, and it raises further questions over the security of the database.
"It also attacks the Government's flawed use of confidentiality agreements, which have undermined proper scrutiny.
"Tragically we shall never know, and we can be sure this Government will never tell us, how many lives could have been saved, and how many people could have been treated better or more speedily but for the Government's wilful incompetence.
"Improving patient care must be the benchmark - ministers seem to have forgotten that. Alan Johnson must be called to account."
A spokesman for the Department of Health said: "New IT systems in the NHS are delivering better, safer and faster care.
"Current costs have declined because of the delays to implementation due mainly to adding extra functions to the system.
"Costs are also controlled by the contracts which only pay to providers once the service has been successfully delivered."
Dr Vivienne Nathanson, head of science and ethics at the British Medical Association (BMA), said: "This report highlights many of the issues the BMA has raised over the years concerning the NHS National Programme for IT, such as concerns over cost, reliability and security.
"With the UK deep in recession the Government must ensure that Connecting for Health confronts the lessons of the past - the NHS IT project can't be paid for with a blank cheque."
But Dr Nathanson said that, despite the problems, "we must not lose sight of the potential benefits that could be delivered in terms of patient safety".
Liberal Democrat health spokesman Norman Lamb said: "This report shows what a disaster the whole flawed programme has been from the start.
"The Government has imposed this programme on local health authorities despite the fact that there was no proper business case and no clinical assessment of what was needed."
Dr Peter Carter, general secretary of the Royal College of Nursing (RCN), said: "This latest report on NHS IT doesn't fill us with confidence.
"The programme is already seriously over budget with costs spiralling from a projected £6.4 billion to an estimated £12.4 billion. This must not be allowed to continue."