in years of case.
</p></dd>
<dt><code class="code">parity</code></dt>
<dd><p>Count.
</p></dd>
<dt><code class="code">induced</code></dt>
<dd><p>Number of prior induced abortions, grouped into “0”, “1”, or “2 or more”.
</p></dd>
<dt><code class="code">case_status</code></dt>
<dd><p>0 = control, 1 = case.
</p></dd>
<dt><code class="code">spontaneous</code></dt>
<dd><p>Number of prior spontaneous abortions, grouped into “0”, “1”, or “2 or more”.
</p></dd>
<dt><code class="code">stratum<