NHS Digital is reviewing a technology that identifies new people who could be at risk of Covid-19 after it incorrectly identified groups of women as needing to shield.

The QCovid risk assessment model flagged some women previously diagnosed with gestational diabetes as being at “high risk” of coronavirus on a “precautionary basis”, a statement from NHS Digital said.

“However, because the risk assessment is based on routinely coded data from multiple systems some women may have been identified as having diabetes when in fact they had gestational diabetes,” the statement added.

“Others may have incomplete data in which case the risk tool may have defaulted, on a precautionary basis, to a higher level of risk for that category and this may influence the overall assessment results.”

An “active review” of the algorithm is underway with further information expected to be communicated to affected women soon.

The assessment tool uses a combination of risk factors based on medical records to determine whether somebody may be more vulnerable than was previously understood.

It is used to predict on a population basis whether adults with a combination of risk factors may be at more serious risk from Covid-19, enabling them to be flagged to clinicians for priority access to vaccination, alongside appropriate advice and support.

These individuals will be added to the Shielded Patient List on a precautionary basis and to enable rapid vaccination.

But following the launch of the tool last week some women were sent letters advising them they should be on the Shielded Patient List.

“Some women with previous gestational diabetes have been identified by the QCovid model as being at high risk,” NHS Digital said in a statement.

“This will be appropriate for many as the model performs an individual assessment based on a wide range of risk factors, and also considers an individual’s risk in comparison to others of the same age and sex.”

Diabetes is a risk factor for Covid-19 and has been included in the QCovid model. Women who have previously been diagnosed with gestational diabetes are at an increased risk of developing type 2 diabetes.

All patients identified through the risk assessment will be sent a letter from NHS England explaining their risk factors identify them as high clinical risk.

They will be invited to receive a Covid-19 vaccine as soon as possible if they haven’t already had the jab, and will be given advice on precautionary measures, including shielding.

The government has extended the current shielding guidance until 31 March.


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