an>
<span>    <span class="va">hos.cat</span> <span class="op">==</span> <span class="st">"US:other"</span> <span class="op">~</span> <span class="st">"{.included} other US patients"</span></span>
<span>  <span class="op">)</span> <span class="op"><a href="../reference/pipe.html">%&gt;%</a></span></span>
<span>  <span class="fu"><a href="https://dplyr.tidyverse.org/reference/group_by.html" class="external-link">group_by</a></span><span class="op">(</span><span class="va">treat</span>, .messages<span class="