A miscarriage of diagnosis

PCR testing for COVID aims to  detect individuals who have a high likelihood of being infectious. False positive test results have more than one cause in PCR testing and productive conversations about them require these categories to be distinguished. The operational false positive rate refers to the rate of error across the whole process.  ThisContinue reading “A miscarriage of diagnosis”

Evidence for and against false positive COVID ‘cases’ in July and August

For False positives: I am working full time on gathering evidence that we have had a significant false positive issue. Listed is the current evidence. This is a live post that I will add to as I get more information in: Characteristics of patients diagnosed with COVID March April 60% were over 60yrs old. JulyContinue reading “Evidence for and against false positive COVID ‘cases’ in July and August”

Why are we seeing an increase in cases?

When we break a recent record for the number of COVID cases we have dramatic headlines.  On 7th Sept there were 2,048 new cases in the UK with 2,988 the day before up from around 1,500-1,900 in the preceding days.  This has created a spike over and above the already upward trend.  (I believe theContinue reading “Why are we seeing an increase in cases?”

Variation in the false positive rate

There are numerous factors that can contribute to a false positive result.  We understand some more than others.  Error can creep in right from the moment the swab is opened until it passes quality control checks in the lab.  Examples we understand include other RNA being present from a different source and cross contamination. EachContinue reading “Variation in the false positive rate”