Nearly a third of all NHS Scotland buildings need repairs and in some board areas - including Greater Glasgow and Clyde, Lothian, Tayside and Dumfries and Galloway - 50 per cent of the maintenance backlog is classed as "high risk and significant"

Audit Scotland's report, NHS in Scotland 2016, lays bare the extent of the health service's problem with ageing buildings.

While the number of buildings needing significant attention has reduced slightly, five per cent still require major investment. Overall, 44 per cent of the NHS Estate needs high risk and significant maintenance as of 2015, down from 47 per cent in 2014.

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Some board areas such as NHS Ayrshire and Arran, and Orkney have as little as 50 per cent of their buildings in good condition - although Balfour Hospital in Orkney is to be replaced.

The report also points out that some of these buildings are underused, with nearly a fifth of properties Scotland-wide classed as underutilised.

The public spending watchdog says that by last year the total cost of outstanding maintenance required to bring buildings up to an adequate standard across NHS Scotland was £898 million.

Audit Scotland says NHS boards are planning around £2.8 billion investment over the next five years, but much of this relates to property, medical and IT equipment and vehicles.

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The capital budget will more than double from £202.5 million in 2015/6 to £494.5 million in 2016/7, but the report says the increase will largely be spent on four new facilities. The Royal Hospital for Sick Children and Department of Clinical Neurosciences in Edinburgh, the Dumfries and Galloway Royal Infirmary, the new Scottish National Blood transfusion service centre and a new hospital in Orkney will together cost £215 million, after which the Scottish Government has said the capital budget will drop again.

Audit Scotland says NHS boards face a challenge in balancing the continuing need for high quality hospitals with shifting investment into community-based care. £290 million currently allocated to developing new models of care in the community.

The report says the Scottish Government should set out its plans for squaring this circle. "A clear national strategy is required for capital investment that will support a shift in the balance of care," the authors conclude.

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A spokeswoman for the British Medical Association in Scotland said: “Whilst it is good to see the report acknowledges there has been some improvements in the management and physical condition of property assets we know there is considerable variation in standards across board areas both in terms of age of properties, their condition, maintenance and levels of use.

“Where staff are working in very old buildings that may be overcrowded and not designed for the type of care they are delivering that can have an effect on the morale of staff and how they feel about their working conditions. We would also be concerned that outdated properties could impact on doctors’ ability to deliver effective patient care.”