The experts writing in the BMJ also question the companies’ claims of accuracy due to the limited information they have published.
Professor Jon Deeks, who advises the WHO and led the first systematic review of the studies supporting the antibody tests, said: “We don’t have much data, and we can’t trust any of it.”
Roche, whose test was the first to be validated, initially boasted that its test had 100 per cent sensitivity, the ability to correctly identify positive samples, and more than 99.8 per cent specificity – the ability to correctly identify negative samples.
Data subsequently released from PHE’s evaluation showed that although 100 per cent of samples taken from individuals who had not had Covid-19 accurately came back as negative, 16 per cent of samples taken from people who had had the virus did not show up as positive.
The BMJ article also called for more detail on how accurate the test is both by age and racial grouping. “Those who are at highest risk of death from this infection are elderly people, those from black and minority ethnic groups, and immuno-compromised people,” it said.
“There are currently no data showing the performance of the tests in these groups.”
The Department of Health and Social Care said: “We do not currently know how long an antibody response to the virus lasts, nor whether having antibodies means a person cannot transmit it to others.”
However, it reiterated its view that antibody testing “will play an increasingly important role as we move into the next phase of our response to this pandemic”.
PHE said its evaluations had “been completed in record time using the samples and tests that were available to us. We are confident that the volume of samples and the methodology was of a high standard”.
A spokesman for Roche Diagnostics UK said: “We are rolling out antibody tests to the NHS as part of the crucial next step in understanding the spread of this virus, and providing greater confidence and reassurance as we move into the next phase of our response to this pandemic.”