An NHS computer system intended to revolutionise patient care has so many software flaws that seriously ill or badly injured patients are at risk of being inaccurately diagnosed, according to an internal health service document.

An assessment of the system at the first hospital to launch it, the Royal Free Hampstead NHS Trust in north London, details a catalogue of software glitches and design faults. It warns that the problems pose a possible “risk to patients by underestimation of clinical condition”.

According to the document, the system, which is being used in the accident and emergency department, is routinely crashing, patient information is intermittently “lost” and some staff are reverting to pen and paper. Extra staff have been drafted in to help cope.

Tony Collins, executive editor of Computer Weekly, said the document, disclosed by an NHS employee, warned that some of the problems could “continue indefinitely”.

He said: “This is the centrepiece of the Connecting for Health programme [the government’s plan to computerise NHS records] and it isn’t working properly.”

Hospital officials said this weekend that continuing problems were being “vigorously” pursued with the contractors while staff were being vigilant to ensure patient safety was not compromised.

The report is the latest setback for the £12 billion Connecting for Health programme, which was meant to provide a single nationwide IT system for the NHS containing records for every patient by 2010.

While some elements of the programme have been introduced ahead of schedule, the patient record system has been beset with delays and software problems.

Last June the Royal Free became the first trust to launch the most advanced version. To protect patient confidentiality, records can be accessed only with a swipe card and a code.

The launch was a key test for Connecting for Health, which has faced questions about the reliability of its systems and whether patient confidentiality could be easily compromised with computerised records. Two months after the launch there were reports of missing data and delays in booking patient appointments.

Now an assessment of the new system at the Royal Free has uncovered a series of problems, which appear to be unlikely to be fixed in the short term.

The Royal Free Hampstead NHS Trust said the implementation of the new system was initially better than expected but there were continuing problems that would “take some time” to rectify.

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