footnote-ref" id="fnref2"><sup>2</sup></a>, which notes:</p>
<blockquote>
<p>To lead to an informative estimator, this cut-off, though theoretically arbitrary, must be chosen to reflect the temporal dynamic range of the test for recent infection; i.e. at a time T post infection, the overwhelming majority of infected people should no longer be testing “recent”, and furthermore, T should not be larger than necessary to achieve this criterion.<a href="#fn3" class="footnote-ref" id="fnref3"><sup>3</sup></a