The Summary Care Records database - which is central to the government's plans to create health records for 50 million people - contains inaccuracies and omissions that make it difficult for doctors to trust it as a single source of truth, according to a confidential draft report.
The findings by researchers at University College London, are likely to reinforce the concerns of the British Medical Association which has called for a halt to the "rushed" rollout of the "imperfect" Summary Care Record scheme.
The Government launched Summary Care Records to help doctors and nurses make better clinical decisions. The aim is for clinicians and out-of-hours doctors to have access, particularly in an emergency, to a central record of a patient's allergies, medications and adverse reactions to drugs.
But the researchers at University College, London, found examples where the Summary Care Records central database failed to indicate a patient's allergies or adverse reactions to drugs, and listed "current" medication that the patient wasn't taking.
The database also indicated allergies or adverse reactions to drugs the patient did not have.
Inaccurate information in the central database came from uploads of patient records by GP practices.
Patients unharmed - because doctors didn't trust the SCR database
Researchers at UCL found no evidence that incomplete or inaccurate data on the SCR database had led to patients to coming to harm - but precisely because doctors did not trust the new system as a single source of truth, and took extra time to double-check details of medications and allergies.
No evidence of safer care
The researchers found no direct evidence that the care records system led to safer care, though they said that access to the database may reduce some rare medication errors. There was no clear evidence that consultations between doctors and patients are quicker - and in some cases use of summary care records made consultations longer.
But researchers also found that when central records are accurate, they can be useful for clinicians, particularly when patients are poor at communicating or, if they are on multiple medications, cannot remember what they are.
1.2 million summary care records created so far
The Summary Care Records scheme is one of the main reasons for the £12.7bn National Programme for IT [NPfIT], which was launched by the Blair government in 2002.
By the end of February 2010, about a third of the 152 Primary Care Trusts in England had begun mailing leaflets on Summary Care Records to nearly nine million patients, of whom fewer than 15,000 had opted out of having their health data uploaded.
About 1.2 million summary care records have already been created. CfH's internal target of one million SCRs was reached on 12 January 2010.
Setting too high data quality standards stops GPs joining the SCR scheme
NHS Connecting for Health requires that GP practices meet minimum standards of data quality before they can upload records to the NHS data "spine".
But officials at the Department of Health are concerned that if they set the standards of data quality that are too high, only small numbers of GP Practices will upload their data.
Until there is a critical mass of patients on the system, few doctors will use it.
NHS Connecting for Health commissioned a series of reports from University College London, so far costing about £723,000 to inform the national roll-out of the Summary Care Records.
NHS Connecting for Health has continued the scheme without waiting for the reports to be completed.
The final UCL report, which is due to be published next month, is expected to make clear that NHS Connecting for Health is a politically-driven organisation whose dedicated staff have strong support from primary care trusts for delivering Summary Care Records - whatever the difficulties.
The problems so far include a low take-up of the scheme by hospital clinicians. UCL researchers found that about a third of GP practices in some PCT areas were using systems that were never likely to be compliant with the Summary Care Record central system.
The final report may ask whether the government founded the SCR on an unrealistic assumption: that the centralised database could ever be a single source of truth.
The Department of Health declined to comment on the report ahead of its official publication next month, but told The Times that errors resulted from problems with GPs' original records, rather than the system itself.