n class="va">x4</span> <span class="op">+</span> <span class="va">x5</span> <span class="op">+</span> <span class="va">group</span>,</span>
<span class="r-in">                 data<span class="op">=</span><span class="va">sim_dat</span>, x<span class="op">=</span><span class="cn">TRUE</span><span class="op">)</span></span>
<span class="r-in"></span>
<span class="r-in"><span class="co"># using direct adjustment with asymptotic confidence intervals</span></span>
<span class="r-in"><span class="va">adjsurv</sp