An indeterminate result means that the pooled test result is neither positive nor negative—the test cannot provide a clear result. This occasionally occurs when the sample’s quality is low.
An unusable result means that the pooled sample was damaged or otherwise physically flawed. The lab received the tube, but they could not run the sample. This could happen if the tube contains the wrong number of swabs, the lab receives the tube outside of the 72-hour window, or the tube was damaged during transit.
You can review additional information about unusable results here.
You can review additional information about indeterminate results here.