The much vaunted national electronic patient records system will not be fully introduced until 2014-15, four years behind schedule, according to the National Audit office (NAO).
The NAO said "serious delays" surrounding the new software for the National Programme for IT in the NHS were largely to blame, although it also said the government had underestimated the challenges involved.
It found that all elements of the £12.7bn programme were advancing, with some complete, but the original predictions for the Care Records Service were "unachievable, raised unrealistic expectations and put confidence in the programme at risk".
Lorenzo, the software planned for the North, Midlands and East, was especially delayed and had forced some trusts to take an interim system, the report found.
The IT programme involves four main projects: a centralised electronic medical record system for 50 million patients; an online "choose and book" system for booking hospital appointments - deployment of which, according to today's report, is nearly complete; electronic prescriptions; and fast network links between NHS organisations.
When complete the system is expected to link more than 30,000 GPs in England to almost 300 hospitals.