But data suggests that the test performs worse in the real world. Liverpool was the first city to pilot the test for mass testing of people without symptoms – about 125,000 residents took the tests between 6 November and 9 December. Of those, 897 people who did not know they had the virus tested positive. However, tests in the field missed 60% of infections in people who were self-swabbing.
This paragraph stands out in particular.