(Photo by Matthias Hangst/Getty Images) A research team at Beth Israel Deaconess Medical Center has developed a mathematical model to estimate the false negative rate for COVID-19 tests. According to a study published earlier this month in Clinical Infectious Diseases, the assay limit of detection (or the smallest amount of viral DNA detectable that a test will catch 95% or more of the time) meaningfully affects clinical performance of COVID-19 tests. The highest LoDs on the market will miss a majority of infected patients, the researchers found. "For getting back to business as usual, we all agree we've got to massively ramp up testing to figure out who's negative and who's infectious – but that's only going to work optimally if you can catch all the positive cases," said corresponding coauthor Dr. James E. Kirby, director of the Clinical Microbiology Laboratories at BIDMC, in a press release announcing the findings.