Is Florida’s COVID-19 positivity rate accurate? Labs not reporting negative test results

SARASOTA, Fla. (WWSB) - Coronavirus cases continue to rise in Florida, but there’s now reports that some of these numbers are not being calculated accurately. Hundreds of facilities across the state are reporting a 100% positivity rate for COVID-19 test results. That means, every single person who got tested at these hospitals or labs, tested positive. This is not accurate.

No local hospitals or big laboratories have reported inaccurate data like this, but other labs like Quest Diagnostic did fall under this list. They’re positivity rate was 100% when in reality, only 25% of their cases are positive.

“This is a real problem because the percentage positive ratio is an important metric for reopening the economy and schools. If you add to the numerator and not to the denominator, you’re biasing that ratio upwards, so we’re getting misleading information. Even worse, now that people know about this, this is seriously undermining the credibility of the Florida Department of Health statistics, so we don’t really know what’s accurate and what’s not accurate,” explained Dr. Rebel Cole, a business professor at Florida Atlantic University, which is about to publish its own data tracker.

The Florida Department of Health has confirmed that close to 400 laboratories were not reporting negative COVID-19 test results to them.

“All COVID-19 cases are confirmed through diagnostic and antigen testing and then reported to the state by the labs performing the testing. Private and public laboratories are required to report positive and negative test results to the state immediately,” the Florida Department of Health said Wednesday in a written statement.

These labs are mostly small, independent labs or small labs within big hospitals, but they make up a big portion of the positivity percentage for the state. The exclusion of negatives has the potential to skew a key statistic known as the positivity rate, or the percent of total tests that are positive, an indicator of community spread - which is what officials use to determine if they should continue re-opening the economy or shut it down again.

“There’s no question that this disease is growing greatly, and even if the negative test results weren’t reported, which is not the way to do things, the fact that we have positives means it is real and is spreading. It’s just the context and the way it’s being presented that needs to be improved. They can’t let that happen,” said Dr. Jay Wolfson, a Public Health Medicine Professor at the University of South Florida.

The state says it’s because labs are used to only reporting positive results, not negative results when it comes to diseases or viruses – but doctors say this has just caused confusion all around.

“But that’s not a good enough reason. That’s because for one thing we are in a pandemic. We need to know what the base is. That’s just as important as knowing who is testing positive or who is testing negative. How many people have we tested and what are their results, but the state should have in their system the capacity to screen incoming data. Otherwise, we are missing a piece, and we are adding confusion for people, which creates a lack of trust,” explained Dr. Jay Wolfson.

The Florida Department of Health says it is now working with all of these labs to make sure all data is reported, and will be adjusting the positivity percentages appropriately.