OKEECHOBEE — Last week, news media in Florida discovered some of the smaller testing labs apparently had only positive COVID-19 tests logged in Florida Department of Health (FDOH) data, although they are required to report both positive and negative. While this does not change the number of positive tests, it could change the positivity rate.

In a statement released to media, FDOH explained: “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. In recent days, the Florida Department of Health noticed that some smaller, private labs weren’t reporting negative test result data to the state. The department immediately began working with those labs to ensure that all results were being reported in order to provide comprehensive and transparent data. As the state continues to receive results from various labs, the department will continue educating these labs on proper protocol for reporting COVID-19 test results.”

Did the data from the labs that did not report any negatives skew Florida’s positivity rate?

FDOH has reported more than 3 million people have been tested in Florida since March. However, some people may have been counted more than once. Staff at long-term care facilities are required to be tested every two weeks. Some first responders who believe they may have been exposed to a COVID-19 positive patient may have been tested more than once. According to FDOH, all of those tests are included in the total until that person tests positive. Once a person tests positive, all other tests — both positive and negative — for that person are not added to the FDOH dashboard totals. First responders and health professionals who test positive must be tested negative twice before being cleared to return to work. Those additional tests are not added to the dashboard totals.

The FDOH COVID-19 Testing by Laboratory report is updated daily. The report of July 20 was 25 pages with about 45 labs listed per page.

The report shows the larger labs reported positives and negatives fairly close to the state average while some of the labs reporting just a few tests had 100% positives.

As of the July 20 report, each of the labs that reported 100% positives (with no negatives) had between one and 488 tests. Many of those labs reported only one test (positive) each. As of that report, the total number of positive tests reported by the labs that had no negatives was 5,426.

As of July 20, FDOH reported 3,055,922 tests in Florida, with 360,394 positive, for a positivity rate of 11.79%.

If you subtract the labs that only reported positive results, the positivity rate would be 11.63%.

The July 20 report indicated the seven largest testing labs accounted for 2.25 million tests, with positives ranging from 3% to 12%. Quest Diagnostics in Tampa reported 594,470 tests with 12% positive. Laboratory Corporation reported 545,061 tests with 12% positive. Bio Reference Laboratories Inc. reported 398,955 tests with 15% positive. Genetwork reported 330,293 tests with 12% positive. Realtox Labs LLC reported 163,953 with 12% positive. Advent Health reported 111,635 with 12% positive. Northwest Laboratory reported 110,037 with 3% positive.