Because Health only uses COVID-19 tests that have received either Food and Drug Administration (FDA) approval or Emergency Use Authorization (EUA). These approved tests minimize the chance of inaccurate, false positive, or false-negative results. The FDA has found that tests that meet certain standards are of superior quality and have high sensitivity and specificity* (measurements of accuracy).
Because Health will not use tests that have been shown to have low sensitivity and specificity. There are other antibody tests on the market that have not received either FDA approval or EUA. Many of these tests can result in high rates of false positives and false negatives.
These poor quality tests can worsen the COVID-19 pandemic by providing false reassurance to those who have the infection or by causing those who do not have it to use critical resources.
*Actual sensitivity and specificity may vary between test manufacturers. A sample that is not properly collected may also result in an inaccurate result.