Weekly laboratory confirmed COVID-19 case rates per 100,000 population, tested under (a) Pillar 1 and (b) Pillar 2, by PHE Centre
Data from PHE spreadsheet available here. (Using the sheet labelled “Figure 6. Cases rates by PHEC”)
Pillar one and pillar two positive tests
Pillar one (p1) tests are conducted by the NHS. Pillar two (p2) are tests conducted outside of a hospital. Subjects tested under p1 are typically either symptomatic patients or key workers. The criteria for testing under p2 are not made clear.
The patterns in the East Midlands and Yorkshire are anomalous as both show a fall in p1 confirmed cases with a rise in p2 confirmed cases.
If pillar two tests are conducted on a random sample of individuals with no other indications of infection then the false positive rate depends on the prevalence in the sample. If the prevalence is below 1% then even highly reliable tests will typically produce more false positives than true positives. The calculations are simple to perform if estimates of test sensitivity, specificity and population (or within sample) prevalence can be made available.
Raw data in convenient format
Download the reformatted data from here