/figure-html/contraceptives-plot-1.png" width="576" style="display: block; margin: auto;"></p>
<p>As we can see from above, 90% power would have been achieved if the
common odds ratio was estimated to be approximately 1.25. To compute the
exact effect size, we employ the <code class="sourceCode r">stats<span class="sc">::</span><span class="fu">uniroot</span>()</code>
function.</p>
<div class="sourceCode" id="cb14"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">target_p