Excessive death rates at five hospital trusts in the West Midlands should be probed by the Government, one of Britain’s leading experts on the subject has said.

The Department for Health insisted it is already taking “tough” action against underperforming hospitals after Professor Sir Brian Jarman said thousands more patients had died between 2007 and 2008 than would normally be expected at 25 hospital trusts in the UK.

Sir Brian, a former member of an inquiry into the deaths of heart patients at Bristol Royal Infirmary who is now an emeritus professor at London’s Imperial College School of Medicine, said that after ten years of “no action, I needed to say something”.

According to Sir Brian’s research, trusts in England with a higher than expected HSMR included: George Eliot Hospital NHS Trust, Heart Of England NHS Foundation Trust, Mid Staffordshire NHS Foundation Trust, University Hospital Birmingham NHS Foundation Trust and University Hospitals Coventry and Warwickshire NHS Trust.

He warned current regulation is “fundamentally flawed” but added that high death rates do not necessarily prove hospitals are doing anything wrong.

He said: “My main concern is that the Government only focuses on self-inspection rather than launching wider inquiries. That is why I have decided to take action.

“An investigation may not prove anything is being done wrong but it could still boost our ability to reduce death rates.”

Sir Brian said each of the trusts he highlighted had at least 150 more deaths than expected in the year 2007-08. Across the 25 trusts, there were 4,600 unexpected deaths in total.

In an investigation into hospital death rates, the professor calls on the Government to ask the Care Quality Commission (CQC) to probe each of the trusts rather than relying on self-assessments.

Sir Brian, a former British Medical Association president, added: “The regulator uses a method which I think is fundamentally flawed, which is that only 20% of hospitals are inspected every year.

“They are assessing 20% of the cases in the hospital. So that’s 20% of 20% which is 4%.

“But when you look at that 4% and see whether the self-assessment agrees with the actual on-site inspection for the hospitals that are at risk, two-thirds of the self-reporting is in fact incorrect.”

The Government defended its record on hospital regulation.

A Department of Health spokesman said: “We are confident that any concerns about under performing hospitals will be thoroughly investigated by the regulator, the Care Quality Commission. We have armed them with powers to take tough enforcement action to make sure all hospitals give patients high quality care.

“The CQC has conducted a regional review of all trusts identified as having high HSMRs (hospital standardised mortality ratios) and the lowest patient safety scores. It confirmed in January that, at that time, they had no current concerns about these trusts such that would require intervention similar to that of Basildon.”

Richard Hamblin, director of intelligence at the Care Quality Commission (CQC), said: “As Professor Jarman has said, a higher than expected mortality rate does not prove a hospital is doing anything wrong.

“These figures need to be considered as part of a wider picture.

“It is over-simplistic to say that a mortality rate across an entire trust is a direct indicator of quality of care. We have found reasons for concern at trusts with both high and low mortality rates.

“NHS trusts are complex organisations, seeing thousands of patients every day across a range of different sites and specialities. Variation exists not just between trusts, but within them.

“CQC looks closely at the mortality rates of every trust in England alongside a range of other data, such as readmission rates, infection rates and reported incidents, as well as information from our inspections, the public and other organisations.

“It is all of this together that gives a picture of performance. We do not rely on trusts’ self-assessment.”