Sensitivity vs. Limit of Detection of rapid antigen tests
Not necessarily. Sensitivity and specificity are decision criterion-based measures. They are not actually separable from another, they are a consequence of choosing a threshold at which to say &quot;the test reports positive&quot; or &quot;the test reports negative&quot;, a consequence of this binary result. As such they are weighed against each other. You can always make a test with 100% sensitivity as long as you always report &quot;Yes&quot;. You can always make a test with 100% specificity as long as you always report &quot;No&quot;.
Similarly, you can define what it means to have reached a limit of detection, but this need not be the same trade-off as the one you use for sensitivity and specificity. For example, you might declare this as the point where your readout is &quot;significantly greater&quot;  than baseline in a collection of known positives vs known negatives. But if you set your decision threshold right at that level of detection, you may still have, let's say, only 50% specificity at that level and accept too many false-positives, so you set a different decision criteria.
They are apples and oranges, there is no reason they need to correspond.