A new study from Boston Children’s Hospital and the Massachusetts Department of Health compared one of the latest rapid antigen tests for COVID-19—the Abbott BinaxNOW—with a highly accurate PCR test in a high-volume, drive-thru testing environment. They found that the rapid test detected almost all adults who tested positive by PCR if they had had symptoms lasting seven days or less. In symptomatic children with less than seven days of symptoms, the test picked up about 85 percent of true positive cases.