Skip to main content

Coronavirus: Screening

Question for Department of Health and Social Care

UIN 130141, tabled on 15 December 2020

To ask the Secretary of State for Health and Social Care, what the current rate is for false (a) positives and (b) negatives from (i) PCR and (ii) lateral flow covid-19 tests.

This answer is the replacement for a previous holding answer.

Answered on

28 January 2021

The current tests are very specific and the risk of false positives where the test is reacting to other viruses is extremely low. Like any diagnostic test there is a possibility of a false negative or false positive result, but this is very small. Independent, confirmatory testing of positive samples indicates a test specificity that exceeds 99.3% or a false positive rate of 1% and additional guidance has been provided to laboratories to reduce the rate even further.

Lateral flow tests go through a rigorous evaluation by the country’s leading scientists with the latest data showing a sensitivity of 57.5% generally and 84.3% in people with high viral loads. They are accurate, reliable and successfully identify those with COVID-19 who are asymptomatic and could pass on the virus.

Named day
Named day questions only occur in the House of Commons. The MP tabling the question specifies the date on which they should receive an answer. MPs may not table more than five named day questions on a single day.