 class="op">=</span> <span class="va">pbc2.id</span><span class="op">)</span></span></code></pre></div>
<p>We aim to assess the strength of the association between the risk of
the composite event and the serum bilirubin level. We will describe the
patient-specific profiles over time for this biomarker using a linear
mixed-effects model, where we include an intercept in both the fixed and
random effects, as well as the linear and quadratic time effects. In the
fixed effects, we also include the interaction o