INDEPENDENT inspectors are to be sent into one of Scotland's biggest health boards after a "rapid" investigation was ordered into high death rates at two major hospitals.

The Scottish Government is to publish the findings on potential safety issues after the team report back by the end of the year in NHS Lanarkshire. Monklands Hospital in Airdrie and Wishaw General have recorded the highest levels of mortality in the country, according to new figures.

Monklands, in Health Secretary Alex Neil's constituency, and Wishaw were singled out for their "high standardised mortality ratios" in the official data on hospital deaths published yesterday.

The probe will also take in performance at Hairmyres Hospital in East Kilbride.

The figures showed the SNP administration's drive to cut the rate of patient deaths within 30 days of their hospital admission is sliding.

During last winter, when patients faced long waits in A&E departments as wards ran out of beds, death rates were higher than for the same period in 2011-12.

Clinical director of NHS Scotland Professor Jason Leitch, who has ordered the Lanarkshire probe, indicated it is not just a recent blip, but slow progress reducing death rates in general, which most concerned him in NHS Lanarkshire.

Prof Leitch said he did not believe that a scandal such as Mid-Staffordshire in England, where poor care may have led to the deaths of hundreds, was hidden anywhere in Scotland.

He also said he would be happy for his own Lanarkshire-based family to be treated in Monklands.

However, Prof Leitch described the mortality figures as an alarm which should not be ignored. He said the standardised mortality ratio for Monklands had risen "relatively significantly" in the first three months of the year. The government's figures show it has gone up to 1.38 from 1.14.

He said Hairmyres, the third largest in Lanarkshire, looked as though it was "fundamentally not changing" while Wishaw's ratio was also up between January and March to 1.10 from 0.97. All three hospitals have a higher ratio than Scotland as a whole at 0.92.

Prof Leitch added that he was more concerned about the long term trend in Lanarkshire's hospitals, noting improvement in the mortality ratio at Monklands since the end of 2007 was 4.4%, at Hairmyres 5.2%, at Wishaw 16.9% and across Scotland 11.6%.

"I want to know that all that can be done in these three hospitals is being done," he said.

Mr Leitch said he believed reduction in mortality rates has slowed across Scotland because the easier changes required to improve patient safety, such as tackling hospital infections, has been completed, and the next steps required to increase survival chances are more complex.

He said: "Twelve-hour trolley waits are a bad thing. Those numbers are still small when you compare them to the overall acute admissions. I think unscheduled care requires an action plan and we need to address winter planning. I do not think those small number of unscheduled care changes represents a change in our mortality numbers."

Healthcare Improvement Scotland, which inspects hospitals, has been asked to undertake a rapid assessment of the situation in Lanarkshire and determine if there are underlying issues to be resolved. They are expected to report back by the end of the year.

NHS Lanarkshire's medical director Dr Iain Wallace, said its priority is top quality care. He added: "We welcome th involvement of HIS to undertake an assessment of the local action plans, along with their detailed review to identify any further improvement measures that can be implemented."

Robbie Pearson, director of scrutiny and assurance for Healthcare Improvement Scotland, pledged a rigorous and independent review.