ex-0"></span><h1>Point difference base parameter<a class="headerlink" href="#point-difference-base-parameter" title="Permalink to this headline">¶</a></h1>
<p>The point difference (also called maximum variation) is the maximum absolute difference between the left and right profile values at the same distance from the profile or detector centre:</p>
<div class="math notranslate nohighlight">
\[P(dL) - P(dR)\]</div>
<p>for <em>dR</em> = -<em>dL</em> from the origin as defined by the array or imaging modality