HOUSTON — Positivity rate is one of the ways health officials have been tracking the spread of COVID-19. And on Friday in Texas, the way it's measured is going to change. It will only be calculated using the date a test was taken.
Positivity rates measure the percentage of positive COVID-19 test results at a given time. At the start of the pandemic, the state health department was measuring the positivity rate using the case reported date and lab test reported date. The problem – positive results from backlogged tests started to put those numbers out of whack.
So that method of measuring is going away.
The state later started reporting the positivity rate by the date a test was received, as well as when it was actually taken.
But now starting Friday, health officials are only going to calculate the positivity rate based on the day a test was taken.
“It’s the best method we have because it most closely tracks what the conditions were at the point those people were tested,” said Chris Van Deusen with the Department of State Health Services.
While state health officials are taking away some ways to track positivity rate, they are adding one. They say they’ll start tracking results from antigen tests, which are the rapid tests that are becoming more popular.
They’ll also still track the molecular tests, mostly the PCR – or nasal collection -- tests, but wanted to add tracking for antigen testing.