t">"ph.ecog"</span><span class="op">)</span>, controls <span class="op">=</span> <span class="st">"age"</span><span class="op">)</span></span></span>
<span class="r-msg co"><span class="r-pr">#&gt;</span> =&gt; Processing variable sex</span>
<span class="r-msg co"><span class="r-pr">#&gt;</span> ==&gt; Building Surv object...</span>
<span class="r-msg co"><span class="r-pr">#&gt;</span> ==&gt; Building Cox model...</span>
<span class="r-msg co"><span class="r-pr">#&gt;</span> ==&gt; Done.</span>
<span class