Covid in Scotland: Concern over Test and Protect 'coding error'

A "coding error" led to contact tracing staff in Scotland overestimating the number of people contacted within 24 hours of testing positive for Covid.

Corrected data shows that in some weeks Test and Protect staff failed to contact about half of positive Covid cases in Scotland within that time.

First Minister Nicola Sturgeon said the mistake should not have happened.

But she insisted the Test and Protect system was working to a "very high standard".

Opposition politicians said the error was shocking and called for answers and reassurance.

The Scottish Sun reported that Public Health Scotland revised up the overall number of positive cases waiting more than a day to be interviewed from 8,262 to 15,291.

Meanwhile, contact tracing cases taking more than 24 hours to complete rose from 17,225 to 23,828.

Scottish Conservative leader Douglas Ross said: "To discover the SNP government has been peddling wildly inaccurate data to the public is shocking. We need answers and reassurance on this as a matter of urgency."

Scottish Labour health spokeswoman Monica Lennon said: "After months of claiming that Test and Protect was working well it is now clear that the system was performing even worse than previously indicated."

Scottish Liberal Democrat leader Willie Rennie called for an urgent statement to the Scottish Parliament on how the "suspect statistics" were published.

And Scottish Greens health spokeswoman Alison Johnstone said: "Test and trace is absolutely key to reducing the spread of this deadly virus and providing a route out of endless lockdowns. It cannot do that if it isn't working or the data isn't robust."

Corrected PHS data shows that in five of eight weeks in September and October, Test and Protect staff failed to contact about half of positive cases within 24 hours of being notified of swab results, or within a day of the Test and Protect system being notified.

In one of the eight weeks the proportion of people with positive swabs alerted within 24 hours of Test and Protect being told dropped as low as 41.7%.

Ms Sturgeon told her daily briefing there had been a "coding error" in how PHS classified cases.

"Without going into technical detail it means some cases classed as processed within 0 to 24 hours should have fallen within the 24 to 48 hours," she said.

The first minister said: "The coding error should not have happened. These things do happen in computer systems sometimes. It has been rectified but the figures published today demonstrate that it is working to a very high standard."

The latest figures show that 60.5% of positive cases were contacted within 24 hours, she said.

Ms Sturgeon said the World Health Organisation states that at least 80% of new cases must have their close contacts traced and quarantined within 72 hours of case confirmation.

The latest figures for Scotland show it is in excess of this international standard, with 95.8% completed in that time.

Public Health Scotland said the coding error had not affected any strategic or operational decision-making on the contact tracing programme.