Surge in number of patients in A&E for over 12 hours
The number of patients in A&E for 12 hours or more increased from 117 in the week ending November 3 to 215 patients the following week.
The number of Scots spending more than 12 hours in accident and emergency "rocketed" to 215, the latest weekly figures showed.
While the Scottish Government has set the target of having 95% of patients dealt with within four hours, data for the week ending Sunday November 10 showed this was only achieved 84.6% of the time - the lowest rate since March 2018.
That meant that 4,338 people spent more than four hours in A&E, including 793 who were there for more than eight hours.
Meanwhile the number who were in A&E for 12 hours or more increased from 117 in the week ending November 3 to 215 patients the following week.
In Scotland's largest health board, NHS Greater Glasgow and Clyde, the A&E target was missed for almost one in five patients, with 80.9% being either admitted, transferred or discharged within four hours.
And at the flagship Queen Elizabeth University Hospital almost a third of patients spent more than four hours in the emergency department - with 68.5% seen in the target time.
Across Scotland the target of having 95% of patients admitted, transferred or discharged within four hours has not been met since August 2017.
The new figures come days after data showed NHS England had seen its A&E performance fall to the lowest on record, with 83.6% of patients treated or admitted within four hours.
Liberal Democrat MSP Alex Cole-Hamilton said while Health Secretary Jeane Freeman had made "big promises" on tackling hospital waiting times she "can't escape the fact the SNP Government hasn't met the A&E target for years".
The Lib Dem health spokesman complained that the "number of patients waiting more than 8 and 12 hours has rocketed".
He said: "To offer patients a brighter future, staff must have the resources they need to do their job.
"A good place to start would be for ministers to publish the integrated workforce plan that staff were told would be out last year."
A Scottish Government spokeswoman said: "Scotland's core A&E departments continue to be the best performing in the UK and have been for more than four years despite experiencing continued high attendance levels.
"This is thanks to the ongoing hard work and dedication of our NHS staff who ensure that people get the best care possible.
"We continue to work closely with those health boards facing the greatest challenges to help drive improvements.
"To tackle the particular pressures winter brings, we have invested #10 million to help boards put appropriate steps in place to ensure quality of care, patient safety and access to services are maintained over the winter period."
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