DEATH rates at six Scottish hospitals have been flagged up by a warning system intended to spot potential deficiencies with patient care.

Higher than expected mortality levels are being investigated at the Vale of Leven Hospital, in Alexandria, along with the Royal Alexandra Hospital in Paisley and the Belford Hospital in Fort William.

Rising death rates at three other hospitals remote from city centres have also been flagged-up to health boards on the back of the figures – which have been updated to better reflect the expectations of modern medicine.

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The data raises questions about whether hospitals in more outlying parts have kept up with standards at the same pace as district generals serving larger populations. Professor Jason Leitch, national clinical director with the Scottish Government, said: "I have not seen any evidence yet to make me believe that to be true. I think it is a question worth asking and question worth asking health boards and Healthcare Improvement Scotland."

The new Queen Elizabeth University Hospital in Glasgow, which opened last year, and the Western General in Edinburgh have been applauded for having fewer patient deaths than expected in the latest figures.

The warning system, known as the Hospital Standardised Mortality Ratio (HSMR), works by estimating how many deaths a hospital is likely to see at a given time of year and comparing this to the number of people who die. The case mix and age and social background of patients cared for by different hospitals are taken into account.

Overall across Scotland between January to March 2014 and January to March 2016, hospital mortality fell by 4.5%, the equivalent of 3,000 fewer deaths than predicted.

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However, the latest data also suggested there were more than double the number of expected deaths at the Belford Hospital where 30 people died in the first months of the year.

The Royal Alexandra Hospital in Paisley and the Vale of Leven combined had 389 deaths compared to the anticipated 338.

A spokesman for Healthcare Improvement Scotland, which monitors NHS and care standards, said: “In today’s release of Hospital Standardised Mortality Ratios (HSMR) by ISD, two hospitals – Belford Hospital and Royal Alexandra Hospital/Vale of Leven – have been identified as having a mortality ratio that is significantly higher than the national average between January – March 2016. Three hospitals, Borders General Hospital, Dr Gray’s Hospital and Lorn & Islands Hospital were identified as having an increasing HSMR. In line with our standard process, Healthcare Improvement Scotland has initiated a dialogue with NHS Highland, NHS Greater Glasgow and Clyde, NHS Borders, and NHS Grampian to explore these data further."

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Professor Leitch said it was the first time hospital mortality in Scotland had been calculated using a new method, which effectively created a higher bar. Previously comparisons had been based on hospital performance in 2006, but this has now shifted to 2012.

NHS Highland has already conducted an independent review of all 30 deaths at the Belford.

Dr Rod Harvey, medical director for NHS Highland, said: “This external review has provided reassurance that there is no cause for clinical concern. It has not identified any systematic failures in clinical care which could have contributed to the death of these people during this period of time being looked at.

“Hospital mortality ratios are not in themselves a measure of quality of care. They are however a valuable tool to flag up where some further investigation should be undertaken and therefore must be taken seriously."

More people being admitted for end of life care and the way patients' conditions are recorded are possible explanations for the high death figure, he said.

Experts noted that larger health boards have more resources to verify their mortality data.

NHS GGC said the Vale of Leven and the Royal Alexandra hospitals had been at the forefront of a number of quality improvement campaigns. They continued: "The board is pleased with the performance of the Glasgow Royal Infirmary and the Queen Elizabeth University Hospital and we will continue to focus on improving care. For our Clyde hospitals, our clinicians and local managers, together with Healthcare Improvement Scotland, will work through these findings and a full report will be compiled for the board’s clinical governance committee in due course."