My question to the Secretary of State for Health & Social Care during the Urgent Question on Covid-19: R Rate and Lockdown Measures, 8 June 2020

John Redwood (Wokingham) (Con): Given the Secretary of State’s great success in expanding the number of tests, will we soon have more precise and accurate R figures, along with the other information now accumulated, and is there not a danger, in interpreting back trends, that they are unreliable because of differential test rates?

Secretary of State for Health & Social Care (Matt Hancock): The answer is yes and yes. Survey testing is the most reliable way of assessing the prevalence of the disease and its downward trajectory, because it ​takes into account a randomised approach to working out where the disease is—much like the opinion polls that we are familiar with in this House—because as testing has gone up, inevitably more cases have been found. It is a good thing that more cases have been found, but we need to know the prevalence, which is best done by surveys.