Nicola Sturgeon: 'Coding error' led to wrong Covid test data

The First Minister said a coding error had adversely affected the Test and Protect system statistics after errors were brought to light.

The 'Test and Protect' system was launched in May

At her daily briefing, Ms Sturgeon admitted there had been problems with how the Public Health Scotland (PHS) data was being processed, which suggested more people were being contacted within 24 hours of having a positive Covid test, than was the reality.

However, she said the public should still have faith in the system and said it was working well, and was exceeding the World Health Organisation's (WHO) standard.

Corrected data shows 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. In one of the eight weeks, the proportion of people with positive swabs alerted within 24 hours dropped as low as 41.7 per cent.

Ms Sturgeon said there had been a "coding error" in how PHS classified cases.

"Without going into technical detail, it means some cases classed as processed within zero to 24 hours should have fallen within the 24 to 48 hours and that has changed some of the figures," she said.

“But Public Health Scotland has updated the figures and Test and Protect is working well.”

She added: "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."

Ms Sturgeon said the WHO standard is that 80 per cent of new cases must have their close contacts traced and quarantined within 72 hours of case confirmation.

The latest figures for Scotland show 95.8 per cent completed in that time, with 80 per cent completed within 48 hours "so Test and Protect is exceeding the WHO standard", she said.

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

An urgent question is being asked on the issue in Holyrood this evening by Scottish Labour's Jackie Baillie after concerns the coding error could undermine the public's confidence in the system.

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